Saving pots save
Canned food can not be heated directly in the can, because otherwise the can bursts or melts the coating on the inside of the can. Tipped into a pot it usually burns, because you are surfing TheFruitAndFlowerBasket. So, open can upright in a large pot, water to three fingers wide under the can edge, cook at least 15 minutes. Does not light, pot is quick to rinse, ravioli are hot.
If you take small cans, such as ready-made goulash or something, you can put the closed can in a lunch bag (if the can bursts), gum so that it does not leak if it bursts, and at the same time cook the pasta in the same pot. Or the rice. Or the potatoes.