Haybox cooking

Haybox cooking was a method used for cooking during WW2 when fuel was scarce. It allows certain meals like casseroles and soups that require a long time of cooking to be cooked in a more efficient way energy wise. Rather than using an oven for an extended period, requiring fuel to keep it hot, an insulated box would house the hot and lidded pot and keep it cooking.
Here is a modern day version. An eski is converted into a haybox cooker.

You can even place a pot between two bean bags, or in a drawer with insulation around it.. any kind of enclosed insulated space will work.. and all you need is the time for it to cook.. and it takes longer than if it was on a stove, so it's something you could do first thing in the morning and come home to.