My mother used to make this sauce and throw browned pork chops in for a few minutes and serve them swimming in the sauce. I love, as well, to add a steak or two for extra fun!
In a medium skillet, heat the olive oil over medium heat. Add the onion and garlic slices and season with salt and pepper, to taste. Cook for about 2 minutes then add the fresh tomato, sugar and oregano. Stir to blend and add the canned tomatoes. Cook for an additional few minutes over high heat, stirring from time to time. Taste for seasoning, add the basil leaves.
After the sauce has finished cooking, cook the steaks using your preferred method. Add the steaks to the hot sauce and allow it to sit for at least 10 minutes before serving.
Like any tomato sauce, it always tastes better after it has had a "night's rest" in the refrigerator.