What is a Thermal Cooker & How Does it Work?

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Oh. My. Goodness. If you don’t know what a Thermal Cooker is yet, you are definitely in for a treat.

This is really a powerful kitchen appliance that most people have never heard of.

Honestly, Thermal Cookers are my go-to item. Even over crock pots, even over instant pots. Why? Oh, so many reasons.

I was a crockpot gal for years – I still am in a lot of ways. But then my husband introduced me to a Thermal Cooker.

“A what?” I asked.

He sat it on the counter and I looked at it strangely. No cord or plug. No buttons. No dials. Hmmm. Can’t be worth much.

But, boy, was I wrong. Once he explained it to me and I gave it a go I knew I would never turn back.

And you know what? I. Love. My. Thermal. Cookers. (Yes, I have a few of them! Ok, I just counted, I have 6 of them. 🙂  )

You’re going to want to understand the magic of thermal cookers. It’s a new concept, but I tell you, once you grasp how easily they work you’ll wonder how you’ve lived without one for so long.

They have been a real lifesaver for me in my kitchen and have really given me more freedom in my cooking. Not kidding one bit.

I want to tell you why I love them and also how they work.

 

This is a pretty hefty post with lots of great information. Here’s what’s covered:

• What is a Thermal Cooker?
• Ways to Use a Thermal Cooker
• Top Reasons Why You’ll Love Your Thermal Cooker
• A Simple Breakdown of How to Use a Thermal Cooker
• Some Important Things to Be Aware Of
• Thermal Cooker Recipe Book with Help in How to Use it
• Different Sizes of Thermal Cookers

 

First of all, What is a Thermal Cooker?

This, my friend, is a thermal cooker:

Simply put, it is a cordless, non-electric, portable version of a crockpot.

It’s simply a stainless steel pot that goes inside a thermal outer pot.

And they are as cool as can be.

 

Ways to Use a Thermal Cooker

Just as the name implies, a thermal cooker cooks with thermal heat. In other words, whatever temperature you bring your food to in the inner pot is retained by the properties of the thermal outer pot.

Hang on with me…. it took a bit of explaining from my husband for me to grasp this new concept. I promise that when it clicks for you, you’ll be glad you kept listening!

I will explain down below HOW a thermal cooker works, but for now, I want to tell you why I love them. Imagine this:

SOoooo many ways and places and reasons and events you can use your thermal cooker:

• Use them for your regular family dinners
• Use them to take dinner to other people
• Help provide lots of food for big events
• Use them on campouts (oh my, I can’t say enough about how handy they are on campouts!)
• Take them on picnics
• To the lake
• Boating
• Tailgate parties
• To the beach
• After your kid’s sports tournament
• Disneyland – yup – save money by making dinner in the AM, going and playing all day, come back to the hotel to a nice hot meal
• To new neighbors
• You name it…
• Anywhere you can go, it can go.

Anywhere you can go, your thermal cooker can go with you.

Cooking your food wherever you are, unplugged.

Way awesome.

Because they not only cook your food perfectly, they also keep your food warm for several hours, and they don’t overcook your food.

I can make food in my thermal cooker in the morning, leave it alone on the counter (remember, it doesn’t have to be plugged in) and come back at dinner time and it’s ready to go. Or I can make it in the afternoon, leave it, and come back at dinner and it’s ready to go.

I can take food in a thermal cooker to a new mom, or a sick friend or a new neighbor, any time of the day, and they can eat dinner whenever they feel like. It’s ready when they are.

Magic? Almost.

 

Top Reasons Why You’ll Love Your Thermal Cooker:

1- Thermal cookers are highly portable. They are non-electric – that means you can take them anywhere and the food will still keep cooking.

2- You don’t have to worry about your food overcooking. It won’t happen.

3- Eat whenever you’re ready. You can eat your meal and then leave the remaining food in the thermal cooker for people who need to eat later, and the food is still perfectly ready for them.

4- You save fuel, which is a plus in many situations. It only takes enough fuel to bring your food up to the desired initial heat, then you simply let the thermal cooker keep cooking the food for you without any more need for fuel.

-An added point here – can you imagine the great blessing thermal cookers would be to countries/peoples who have limited fuel, or extremely expensive fuel? Talk about a truly beneficial appliance that needs to get out to the world through humanitarian efforts.

5- I can start dinner at any time of the day. I can make a meal for a neighbor any time of the day, take it to them and give them instructions to just let it sit on their counter and they can eat it anytime they are ready. No fussing about cook time, or juggling a busy schedule to cook food at certain times. I make the food when I have time, take it to them when I have time, and they can eat it whenever they want to.

6- Food items don’t fall apart. The food retains integrity, no matter how long it’s been in the thermal cooker.

7- Highly nutritious meals. Because of the short amount of time spent on the stovetop, and since all the cooking and heat is retained inside with no evaporation, all the goodness stays inside. It entraps flavor, minerals, and nutrients; generates less odor, grease, and smoke in the kitchen. Never overcooks and cleans up easily.

8- Frees up space on your stovetop. OK, this is a huge plus at big family gatherings like at Thanksgiving and Christmas and family birthday parties, for example. Imagine being able to have things cooking while not taking up space on your stovetop. YES. I can have mashed potatoes cooking in one thermal cooker that is over sitting on the counter, the Catalina Chicken cooking in another thermal cooker that is also over sitting on the counter out of the way, and that leaves me all the burners available on my stovetop for other things. Hallelujah.

This is a picture of the meal I cooked for my son’s birthday dinner a couple of weeks ago. I had three thermal cookers sitting on my counter, each cooking different things that I started at different times of the day at my leisure. One had cut up potatoes in it for mashed potatoes, another had green beans cooking in it, and the third had Catalina Chicken cooking in it. THAT MEANS MY STOVETOP HAD THREE EMPTY BURNERS that would have had to have been used if I hadn’t been using thermal cookers.

9- Have breakfast ready when you get up. You can put things like 9-grain cereal, steel-cut oats, etc in your thermal cooker right before bed, and wakeup to fully cooked, totally warm and ready to eat for breakfast. Never overcooked or dried out. (Basic recipe: 2 1/2 cups of grain and 4 cups of water.)

10- Keeps hot food hot and cold food cold. Yep. You read that right. If you put something hot in it, it will retain that heat. If you put something cold in it, it will keep that cold temperature. Think of taking cold pasta or potato salad to a picnic and having it stay the right cold temperature without having to cart it in a cooler with a bunch of ice.

AND, think about putting homemade ice cream in it and having perfectly cold ice cream ready whenever and wherever you are. It’s amazing to think of the possibilities.

12- It’s safe to leave unattended because there is no power or pressure needed to cook. The thermal cooking process requires no further supervision or monitoring. Food can be cooked while you are traveling or socializing at a tailgate party. You can cook with the pot anywhere, anytime and it’s safe to use indoors or out.

13- It saves money because with the convenience of taking thermal cookers with you wherever you go, you save money by having an awesome meal ready to go in crazy situations – like if you’ve been at your son’s baseball tournament all day, or you’ve been traveling and arrive at your destination hungry but don’t want to spend money eating out. It also saves money because after the heated food has been placed inside the outer vacuum pot there is no extra energy needed to maintain the heat or cold for the next 6 to 12 hours.

14- Excellent Preparedness item. Imagine you and your family have gone through a natural disaster, and have little or no access to city fuel. If you have a camp stove and the fuel to run it, you can still cook meals for your family and others like a champ in your thermal cooker. Since it only requires little fuel to bring the food up to the necessary temperature and since it keeps on cooking for hours without any more fuel, it really conserves fuel.

15- Saves time because you’re not constrained to your house/electricity to cook your meal. You can plop your meal in the thermal cooker and take off to your activities – come back and eat when you’re ready, or take the meal with you.

16- The outside of the outer pot stays cool. That means kids can touch it and won’t get burned. It’s also a benefit when you go places and cart the thermal cooker with you in your vehicle. (When you do travel with it, you’ll just want to make sure it is placed securely in your car so it doesn’t tip or that the lid doesn’t get bumped open.)

 

How a Thermal Cooker Works

Now I’m not going to get into the science of it all, I’m just gonna talk like one mom to another, so here it goes…

There are two parts to a thermal cooker-

• the inner stainless steel pot with its lid
• and the outer thermal container with its lid

 

The outer pot of the thermal cooker is insulated and uses the thermal mass of your food from the inner pot to continue the cooking process.

You heat up your food in the inner pot, and then put it in the outer pot to continue cooking.

So, unlike a crockpot that requires continuous power to keep the crock hot to continue cooking your food, once you add a hot inner pot to the outer thermal pot of the thermal cooker, it retains the heat of the food and uses it to continue the cooking process.

Pretty simple. Yet ingenious.

 

Here’s a Simple Breakdown of How to Use a Thermal Cooker

You take out the inner stainless steel pot and fill it with your food items – like soup or stew, or roast, or chicken dinner – and put it on your stovetop and heat your food up to a good rolling boil.

Let it boil for 1-20 minutes – depending on what type of food you have in it (more on this detail down below).

 

 

Then you put the lid on the inner pot, turn off your stovetop, use a hot pad to pick up the inner pot by its handle, and put in into the outer thermal container.

 

 

Then you close the lid on the outer thermal container.

 

 

And move the handle forward to “lock” the lid shut. (Note that it’s not a tight/secure lock.)

 

 

Voila. Dinner will be done soon.

(See more a more detailed tutorial on how to use a thermal cooker here.)

 

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 here.)

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.

Cleaning of your 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.

 

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.

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, What Do You Think?

Are you impressed yet? 🙂

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:

• How to Use a Thermal Cooker
• 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!

 

Here’s to awesome cooking!

 

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