1. Cut the bell pepper into small dice
2. Peel and mince the garlic and onion
3. Drain the tuna.
4. In a large skillet or pot, heat the oil and then add the bell pepper and onion
5. Cut the tomatoes into dice.
6. When the onions become translucent, add 1 tablespoon of tomato paste. Stir regularly
7. Season with crushed garlic, chili pepper, a little salt, and pepper
8. Add water, then let it simmer on low heat for 10 minutes
9. Add the tuna and continue cooking for another 5 minutes