Heat vegetable oil in a deep frying pan over medium heat. Peel and finely chop the onions and garlic. Fry for 3-4 minutes until soft. Add finely chopped chili pepper to taste.
Add the minced meat and fry, stirring occasionally and breaking up lumps with a spatula, until no longer pink (about 5-7 minutes). Season with salt to taste.
Add the tomato slices, stir well, and continue frying over medium heat for 4-5 minutes.
Add the canned beans with their liquid. Stir and warm over medium heat for 2 minutes.
For each tortilla: lay it flat, spread salsa sauce on the inside, spread meat filling on one half, grate cheese over the filling, and roll up tightly from the filled side.
Place all burritos seam-side down on a baking sheet. Melt the cheese by baking at 180 °C (350 °F) for 5-7 minutes until the cheese melts, or microwave for 30-45 seconds per burrito.