In a large, deep pot over medium-high heat, melt the butter and olive oil. Add the chopped onions, garlic, salt, and pepper. Sauté for 3-4 minutes or until the onions are translucent. Stir in the tomato sauce, tomato paste, and water.
1 Tablespoon butter, 2 Tablespoons olive oil, 2 small onions, 2 garlic cloves, 1 1/2 teaspoons salt or to taste, 3/4 teaspoon black pepper, 1 15- ounce can tomato sauce, 2 Tablespoons tomato paste, 3 ½ cups water or broth