Its amazing how many people have food that needs heating stored, but little idea how they’re going to heat it.
And candles are far more useful than many realize for the times that you need just a little light. Bought a bunch of them when a store was going out of business, and had lots of odd colored candles left after people had scarfed all the white ones. Paid about 10 cents each for them.
That was smart to do. Mine are jar candles and I can rig a Sterno stove so it will fit over one and give me a way to warm food if I were to run out of canned heat, which I never will - well, I could sometime after a year.
The very best stove for anyone, to last a lifetime and cook with a small amount of most anything that is biomass, is the “Wood Biomass Stove” that is very heavy and one can cook a meal using several twigs and that's it. That stove is scientific and burns every bit of the small amount of fuel at a high temperature. All that is left is a bit of ash.
It will also use a small amount of charcoal, just a few pieces, and burn every bit of it, again at a high temperature.
I have Kartographer to thank for telling me about this kind of stove. He, of course, made his from scratch, and I bought mine already made.
I have some bushes outside my front door, and could just break off several twigs and that cooks dinner with this stove. Any small pieces of wood from any source is all one needs with this stove. Seashells would also work, any biomass will work.