How to Use a Thermal Cooker

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Ok folks, hold on to your seats. I’m going to show you how amazingly easy it is to use a thermal cooker.

It’s not complicated. You don’t need special recipes to use it.

You just need to know a few fundamental things about how they work and how to use them optimally and you’re good to go!

They are a bit different from most appliances, but I tell you, once you get the gist of things you’ll be sold on using them just like I am…

… and your mind will all of a sudden begin to think of all the things you can do with it…

… and you’ll wonder how you ever lived without one before! 🙂

In this Article There are Several Sections:

• A short schpeel of how to use a thermal cooker
• A simple recipe to use in your thermal cooker
• A visual tutorial of how to use your thermal cooker, making homemade chicken noodle soup
• Our own personal study of the heat retention of the Thermos RPC-4500 thermal cooker (the one shown in this article)
• Are you beginning to see the tremendous value here?
• A few more details to help you understand better
• Some important things to be aware of
• 6 important things to remember when using your thermal cooker
• A recommended recipe book for thermal cookers
• Different brands of thermal cookers
• The different sizes of Thermos brand thermal cookers
• Some more articles to help you with your thermal cooking

 

A short schpeel of how to use a thermal cooker-

(See a visual tutorial below.)

• Fill the inner pot with your recipe ingredients
• Put the inner pot on your stovetop and bring the contents to a boil (time of boiling depends on contents, more on that later)
• Put the lid on the inner pot, take it off the stovetop
• and place the lidded inner pot into the outer thermal pot, and close the outer pot’s lid
• Let the thermal cooker sit for the necessary cooking time (or longer, more on this later)
• When ready to eat, open the outer pot, and open the lid of the inner pot and serve your dinner.

Simply assemble all the ingredients in the stainless thermos inner pot, put it on the stove and bring to a boil. Then remove the inner pot from the stove and place it inside the outer vacuum thermal pot which serves as an insulated thermos container to keep the contents hot.

There is no need to plug in any power cord. The food will continue its thermal cooking process using the retained heat of the food places inside and will continue to cook like a non-electric crockpot. After the required time (e.g. rice 30 min; chicken stock 2 hrs; beef brisket 3.5 hrs), just open the outer thermal pot, and a nutritional and flavorful meal is hot and ready.

 

Here’s a Simple Recipe to Make in Your Thermal Cooker:

 

 

A Visual Tutorial of How to Use a Thermal Cooker, Making Easy Homemade Chicken Noodle Soup:

Step 1 of How to Use a Thermal Cooker:

• Take the inner pot out of the inner pot.
• Put the inner pot on the stove.
• Put in
  • 8 c water
  • 1 lg can cream of chicken soup
  • 8 tsp chicken bouillon
  • 4 Tbl minced dried onion
• and mix well
• Add
  • 1 chicken breast – cut into 1″ strips  –  (The size is important. If your meat pieces are larger, you’ll need to boil longer. It’s not a problem, it’s just for this recipe, to only have to boil for 3 minutes, your meat slices need to be small.)
    • (Be sure your meat is thawed. Never put frozen meat or other frozen food items in your thermal cooker.)
  • 1 1/3 c. carrots, sliced or julienned
  • 1 c. celery, sliced
  • 3/4 c. peas (canned or frozen, let thaw)
• Bring to a boil then add
  • 1/2 lb rice noodles
• Boil all for 3 minutes

 

Step 2 of How to Use a Thermal Cooker:

Put the lid on the inner pot of the thermal cooker, turn off the burner, and put the inner pot inside the thermal insulated outer pot.

 

 

 

Step 3 of How to Use a Thermal Cooker:

Close the lid on the outer thermal insulated pot.

 

 

Step 4 of How to Use a Thermal Cooker:

Bring the handle on the outer pot forward as it lightly locks it shut.

 

 

Step 5 of How to Use a Thermal Cooker:

Let this sit and continue the cooking process on your counter for 2-12 hours. (Or, of course, you can take it with you on a trip, to the beach, a sporting event… and have your dinner ready to eat when you are.)

It’s ready to eat after 2 hours, but the cool thing with thermal cookers is you can eat the food ANYTIME during the period that it retains temperatures above 140*.

SO, that means you can eat your soup in 2 hours…

…or 3 hours…

…or 4 hours…

… or 5, or 6, or 7, or 8, or 9, or 10-12 hours. (All depending on the food you’re cooking, how full the pot is, and what your original temperature was.)

 

Our Own Personal Study of Heat Retention of the Thermos Brand RPC-4500 4.5L  Thermal Cooker:

My husband loves to test things and see how well they work. He tested the Thermos brand RPC-4500 (the one used in this article) and some other thermal cookers and even Wonderboxes to see how they compared in the heat retention department.

I won’t share all the details of the other products, but this is what he found with the Thermos RPC-4500 4.5L:

With a pot being filled full with a recipe like this one – one that has lots of liquid – and having been brought to a full boil for the proper amount of time (3 minutes for this recipe)

• the contents stayed above 160* for 8.5 hours
• and above 140* for 15 hours
  • (140F is the temperature where if kept above bacteria doesn’t grow.)

Pretty impressive!

Mind you, that if your recipe has higher bulk food content and less liquid content (like a pot roast or something) the length of time it will retain heat will differ.

Just make sure you follow the directions and use wisdom and common sense and you’ll be just fine.

 

Are you Beginning to See Some of the Tremendous Value Here??

As I stated in another article I wrote titled “What is a Thermal Cooker & How Does it Work“,

• your food won’t overcook
• it won’t fall apart from sitting a long while
• you can make your food WHEN YOU WANT to
• it will keep cooking safely without your attention
• you can take it anywhere with you
• you can eat the food anytime during the safe temperature window
  • with a Thermos brand thermal cooker, that means up to 10-12 hours, depending on your food item and how full your pot is
    • (If you use a different brand of thermal cooker, your window of safe temperatures can be quite a bit different – meaning, less time. That’s one of the main reasons why I love the Thermos brand the best is because it has such high performance and high quality.)

 

A Fun Picture to Show you:

The day I was making this soup recipe I was also making homemade yogurt. SO, I took a picture of them heating up on the stove at the same time. 🙂

And in the picture above where it shows closing the thermal cooker, you’ll a second closed thermal cooker sitting on the counter. That’s my yogurt during the incubation process!

(Here’s how to learn how to make yogurt in a thermal cooker.)

 

 

OK, Here are a Few More Details to Help You Understand Further:

• One of the rules of Thermal Cookers is you always have to bring your contents to a boil. Once it’s boiled the appropriate length of time, you transfer the inner pot to the thermal outer pot and it’s the energy from that boil that continues to cook it for up to 12 hours.

People ask, ‘do you have to keep it in there for 8-12 hours?’ No. For example, the recipe used in this article finishes cooking in 2 hours, so you can eat it in 2, or 3, or 4, or 5, or 6, or 7, or 8, or 9, or 10-12 hours. (All depending on the food you’re cooking, how full the pot is, and what your original temperature was.)

You’ll want to keep track of that time so that you know you’re in that safety zone that we know that food is safe to eat at. (140F is the temperature where if kept above bacteria doesn’t grow.)

*See the section of this article “Our own personal study of the heat retention of the Thermos RPC-4500 thermal cooker” above

• If you follow the 6 important rules I share down below,  you have up to 10-12 hours of having the food stay hot in the safety zone in your Thermos brand thermal cooker.
  • If you use a different brand of thermal cooker, your window of safe temperatures can be quite a bit different – meaning, less time. That’s one of the main reasons why I love the Thermos brand the best is because it has such high performance and high quality.
  • After 10-12 hours you need to be sure to reheat it or refrigerate it just like you would any other food.

• One of the goals of thermal cooking is to have the pot between 2/3 full to completely full for optimal use – meaning, the more full the thermal cooker is, the more heat mass it has, meaning the longer it will hold the temperature.

 A full pot or one that is at least 3/4’s full is best to maintain the best thermal mass to completely cook foods without any issues. If your recipes are smaller than what would fill pot at least 3/4 full then a smaller capacity thermal cooker would be the better size to serve your cooking needs, or be prepared to open and use your food items in a few short hours.

 

 

6 Important Things to Remember When Using Your Thermal Cooker:

1- Always used thawed food.

Never use things like frozen meat, since doing so will reduce the temperature in your thermal cooker.

2- Always boil your food for the appropriate amount of time before placing the pot in the outer pot.

Your food items, such as your meat and veggies, must be covered in liquid and brought to a full rolling boil for 2-20 minutes (depending on what you’re cooking.)

3- For optimal use, make sure your thermal cooker is at least 3/4 to completely full.

This (along with the proper boiling time) ensures high thermal mass which will ensure your food stays at or above 160 degrees F for the full 8 hours.

4- To ensure food safety, check your food temperature before eating.

If you initially brought your food to a good rolling boil for the proper amount of time, and you kept the thermal cooker closed during it’s cooking time, and used your food before the 10-ish hour time limit was up, your food will keep the appropriate temperature for safe eating.

Be careful when you open your unit up as the food will be hot! Safe serving temperatures according to US commercial kitchen rules are between 145 and 170 degrees.

It’s your responsibility to ensure food safety. If your food temperature is getting low and you still need to have the food to serve later, reheat the food to a good boil and replace it in the thermal cooker. Otherwise, refrigerate your food.

5- If you want to eat dinner at 6:00, be sure to start cooking at or before the necessary time.

A chicken noodle soup recipe like the one shown above will be done cooking and ready to eat in two hours. (But remember, it can stay in your thermal cooker for several more hours and you can eat your meal at any time during that safe temperature time frame.)

A meal with a pot roast in it will take up to eight hours to cook. Just be sure to know how much time your particular meal will take to cook and plan your start time accordingly.

6- No peeking! Avoid any temptation to peek inside as that will let the heat escape and prolong or prevent complete cooking through.

 

 

Some Important Things to be Aware Of

How full should I fill the inner pot with food?

The longer it takes a particular food to cook, the fuller your pot will need to be to gain the maximum thermal mass.

Certain foods take longer to cook than other foods.

For example, pinto beans take a long time to cook. So be sure to have your pot full.

But things like rice don’t take long to cook, so it would be ok for the pot to not be all the way full.

So here’s the rule of thumb: For a thermal cooker to stay hot longer, the pot must be fuller.

How long must my food boil on the stove before putting the inner pot into the outer pot to continue cooking?

The type of food you are cooking determines the length of boiling time.

Meals with meat in it need to boil for a few minutes longer than ones without.

Meals with smaller cuts of meat can boil for just a few minutes while meals with larger cuts of meat will need to boil for up to 25 minutes.

NOTE: Always use thawed meat and food items. Never use frozen meat or food items, as they will lower the temperature in your thermal cooker. (See the 6 Important Things to Remember When Using Your Thermal Cooker above.)

As you cook more and more with your thermal cooker, you’ll get the hang of things and know what to do. I would also highly recommend getting this Thermal Cooker recipe book for more detailed instructions for specific recipes.

What part of the thermal cooker goes on the stove?

Only the inner pot is to be used on your heat source. Never put the outer thermal pot on the stove.

How do I clean my thermal cooker:

Cleaning the inner pot: You can hand wash or use the dishwasher like any other pot.

Cleaning the outer thermal pot: Never submerge. Never in the dishwasher. You simply get a clean wet cloth and wipe it down, inside and out as necessary.

Another rule of thermal cooking is to not peek into or open the thermal cooker because that will let heat escape.

However, if you’re doing this recipe and have the chicken to put in the thermal cooker, then soon after adding the rice to the thermal cooker, you are opening the thermal outer pot to put the rice in. But this isn’t a concern since you are adding heat by way of the rice and things will work out fine.

 

Thermal Cooker Recipe Book with Help in How to Use it

There’s a gal who has put together a really awesome recipe book that shows how to use a thermal cooker in all sorts of ways. I have this recipe book and it really is great. My husband knows the gal who wrote it,  Cindy Miller, and she’s pretty amazing.

You really don’t need new recipes to use in a thermal cooker, what you really need is just a basic understanding of how it works and you can use almost any recipe that you already have in it.  But you might also like to get this recipe book because in it you will be amazed to realize all the things you can do in a thermal cooker that you may have never thought of before.

It’s called “Let’s Make Sense of Thermal Cooking Cookbook”

 

There are Different Brands of Thermal Cookers

There are a few different brands of thermal cookers out there, such as Tiger, Tayama, Sunpentown, Saratoga Jacks, and Thermos, and we’ve tried out most of them. Our two favorite brands are the Saratoga Jacks brand and the Thermos brand. In fact, we are good friends with the folks who provide the Saratoga Jacks brand.

I now only use the Saratoga Jacks brand and the Thermos brand. They are the only two types that we’ve kept after all of these years. We are just impressed with their quality and performance.

And out of these two favorites of mine, the Thermos brand is my absolute favorite, hands down.

The Thermos brand is just a super high-quality item. The inner stainless steel pot feels solid to the touch, meaning it’s well made and not thin (18/8 stainless steel pot that ensures longevity, quality, and excellent food delivery.) I also prefer the handles on the Thermos brand for ease in carrying.

So, since the Thermos brand is my absolute favorite after using other brands, it’s the one I recommend.

 

The Different Sizes of Thermos Thermal Cookers

The smallest is the Thermos 1.5 L

It’s a very popular size. Being just 1.5 liters, it’s great for lunches and 1-2 person meals. Because it is smaller than the other thermal cookers it won’t have as much heat mass, therefore it won’t keep your food hot as long, although still long enough to totally reap the benefits of thermal cooking. While the larger Thermal Cookers can retain a temperature of about 160 degrees F even after 8 hours, the food inside the 1.5 L pot can retain a temperature of about 160 degrees Fahrenheit even after 4 hours. Still a very handy item.

 

This is the one I use most often:

Thermos CC-4500 4.5 L

 

This is a great size for regular family meals as it can serve between 6-10 people. Super handy.

And just so you know, there is another color of this same size Thermal Cooker:

The Thermos RPC-4500 4.5 L

The CC-4500 and the RPC-4500 are initially the same Thermal Cooker. The CC is a US version that is black and silver, and the RPC is an international version with a brown and light bronze-ish color. They both perform equally well.

 

 

And, the double whammy:

The Thermos RPC-6000 6L with TWO inner pots (3 liters each)

OK, this one is a really cool thing. You can cook TWO items in it at once. Like a chicken recipe in one pot and rice in the other. Voila, chicken and rice made in one Thermal Cooker.

You can see how I used this one when we went camping here.

AND, you can order a single tall 6L pot to go with this RPC-6000. It comes in handy when you have large recipes to make…

 

 

Then there’s the biggest of them all:

The Thermos KPS-8000 8 L

THIS is the one I LOVE at big family gatherings like Thanksgiving and such. It’s the one I use to make a bunch of mashed potatoes in. It’s SO cool to be able to peel and chop up the potatoes earlier in the day, bring them up to a boil for a minute or two in the inner stainless steel pot, then put it in the outer thermal pot, close it, and let it sit on my counter the rest of the day while I’m doing other things.

 

**Note that Thermos brand thermal cookers are imported and the packaging and materials inside are geared for the Asian market as Thermos has not localized these cookers for the US market. However, part of the recipe book is in English and the simplicity of use doesn’t require much instruction.

 

 

So, Friend, Does This Help You Better Understand How to Use Thermal Cookers?

If you have any questions feel free to ask. I’m always glad to help.

To help you more, I’ve written a few other posts about Thermal Cookers to help you really get the idea of how great and useful they are:

• What is a Thermal Cooker & How Does it Work?
• How to Make Yogurt in a Thermal Cooker
• Easy Meals to Make While Camping Using a Thermal Cooker
• Homemade Ice Cream on the Go With a Thermal Cooker

I can pretty much guarantee that if you get a Thermal Cooker (or several of them like I have!) and learn how to use it well, you will love it and be so grateful for the benefits it brings to you!

 

Happy thermal cooking!

 

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