Well my experience is just from weekend camping while doing various reenacting, but having a candle stub burning in the socket ring of an American Civil War bayonet for a hour or so does wonders for taking the chill off of a 6×9 foot canvas A tent at night. Those little brass backpackers candle lanterns are also pretty good at the same thing, Our big 12×16 foot double bell wedge pavilion uses up to 4 candle lanterns and if we are camping when it will be getting more than nippy at night we also use a catalytic propane space heater after we extinguish the candles, that was with My wife and I plus 2 little kids, the same group crammed into the “little” A tent and we had no safe place for the candle lanterns so we just used a lot of wool blankets and snuggled up.
Never tried to cook over a candle, even when roughing it at ACW events there was still a communal fire pit, and at events when we or the group we were camping with were NOT roughing it, things were almost posh. Biggest kitchen setup I have been involved with was for a demo center at a big medieval week long event, 4 good sized mud brick ovens a fire pit and a place we dumped the coals from the ovens where you could heat water or do some slow baking. Took us about 16 hours to get the whole kitchen setup built and then we had to fire the ovens overnight to harden them. A week later we had to use sledge hammers to break up the mud shell so we could load the bricks back onto a trailer. Most elaborate kitchen I saw at an event had 2 full gas ovens with range tops that had been setup to run from 20 Lb propane cylinders, each one went through at least one tank a day, and they only had 15-20 people to feed, we fed more people than that better food, cheaper and faster with 2 2 burner Coleman stoves and 1 mud brick oven.
OK, did anyone spot the point to my digression into cooking? I thought I had one when I started, but now I have no idea if I made a point or not. Thank goodness that it is time to head home, 45 minutes to decompress and vegetate with an eBook while riding the bus