Flour tortilla
Cheese (Monterey Jack, mild Cheddar, or Mozzarella)
butter
Fixings (refried beans, leftover rice, sour cream, avocado, or whatever sounds good to you)

Grate a big handful of cheese for each tortilla you're going to be using. Then turn the heat on low under your frying pan and melt about a teaspoon of butter, using a fork to spread it around. When it's all melted, put a tortilla in the pan. Put the cheese on the top of the tortilla and then add the fixings that you'd like to warm up. Then fold the sides together so it looks like a burrito.

Turn the heat up to medium and cover. Check after 3 or 4 minutes because burritos are easy to burn. When the cheese is just starting to melt, turn off the heat but leave the pan (with lid still in place) on the burner. After another minute or two, it should be ready. Now with a spatula, try to get it from the frying pan to a plate without making a mess. Add the sour cream or whatever else you've got and eat with your hands like a hot dog. If you've made a good burrito, though, this is impossible. Too sloppy. You'll need a knife and fork.