In a deep pot on 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. Add tomato sauce, tomato paste, and water.
1 Tablespoon butter, 2 Tablespoons olive oil, 2 small onions, 2 minced garlic cloves, 1 1/2 teaspoons salt or to taste, 3/4 teapoon black pepper, 1 15 ounce can tomato sauce, 2 Tablespoons tomato paste, 3 ½ cups water or broth