Heat 1 tablespoon of olive oil over medium heat in a dutch oven or a large oven-safe pan. Brown steaks on each side. Set aside.
Pour half the tomato sauce and canned tomatoes in the bottom of the dutch oven or pan, put steaks on top, and then add the rest of the canned tomatoes and tomato sauce. Finally, add sliced onions and salt and pepper again if you like.
14-16 oz canned tomatoes, 14-16 oz tomato sauce, 1 onion, sliced
Cover and cook for 2 ½-3 hours.
Serve with mashed potatoes and your favorite veggies.