Thermal cookers are not new and were known as Fireless Cookers a 100 years ago here in the USA. Many old recipe books from that era are available online for free or have been republished and can be bought in book form.
Below are links to the online versions and reprinted versions of a number of cook book/recipe books on fireless cooking which can be used directly in a modern thermal cooker. Some of the old recipe books reference a “radiator” which was often a soap stone or cement disk that was heated up on a stove and then placed in the insulated box under the pot that held the food. The stone radiated heat and helped keep the temperatures up inside the cookers and even allowed for some baking to be done inside the fireless cook box.
The Fireless Cook Book by Author Margaret Mitchell
http://openlibrary.org/books/OL24359…less_cook_book
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The Duplex cook book, containing full instructions for cooking with the Duplex fireless stove
http://openlibrary.org/works/OL78905…plex_cook_book
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Meals That Cook Themselves And Cut The Costs
http://openlibrary.org/works/OL75412…_cut_the_costs
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Book of Caloric Recipes
http://openlibrary.org/works/OL23760…_stove_recipes
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The Fireless Cooker, How to make it, How to use it, What to cook
http://openlibrary.org/books/OL6953828M/High_living
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Fireless Cooker Recipes
http://openlibrary.org/works/OL13849…cooker_recipes
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The Fireless Cooker
http://openlibrary.org/works/OL78867…ireless_cooker
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Superior fireless cookery
http://openlibrary.org/works/OL13842…reless_cookery
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Thermatic Fireless Cooker Recipes – A treatise on the management of the Thermatic fireless cooker, together with over 250 carefully selected recipes.
http://openlibrary.org/works/OL13840…lected_recipes
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The Winston cook book, planned for a family of four
http://openlibrary.org/books/OL24160…family_of_four
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Simple Cooking of Wholesome Food for the Farm Home
http://openlibrary.org/works/OL78973…_the_farm_home
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