Start by cutting the red bell pepper and onion into cubes or strips, then sauté in a pan with a dash of oil and a pinch of salt over medium heat.
Once they are well sautéed, add the diced chicken breast seasoned with salt (If you wish to marinate the chicken with cumin, thyme, etc., you can do so).
Sauté the chicken well, and once done, set it aside on a plate to cool slightly.
Meanwhile, on a clean skillet, place the corn or wheat tortilla and spread the chicken, onion, and pepper mixture on top.
Evenly cover with cheese, place another tortilla on top (Remember, if you prefer, skip the second tortilla and simply fold the first one in half) and let the bottom tortilla brown for about 1 minute. Covering the skillet with a lid can help the cheese melt more efficiently.
After a minute, flip the tortilla using tongs to brown the other side.
Once both tortillas are golden, transfer to a plate.