Back Slow Cooker Spaghetti Sauce Ingredients 1 tablespoon olive oil 1 package (8 oz) sliced fresh mushrooms (3 cups) 2 large onions, chopped (2 cups) 3 cloves garlic, finely chopped 2 cans (15 oz each) tomato sauce 1 can (28 oz) diced tomatoes, undrained 1 can (6 oz) tomato paste 2 tablespoons sugar 1 tablespoon dried basil leaves 1 teaspoon dried oregano leaves 1/2 teaspoon salt 1/2 teaspoon pepper 1/2 teaspoon crushed red pepper flakes Directions Spray 4- to 5-quart slow cooker with cooking spray. In 12-inch skillet, heat oil over medium heat. Add mushrooms, onions and garlic; cook 4 to 5 minutes, stirring occasionally, until onions are tender and translucent. Spoon vegetables into cooker. Stir in remaining ingredients. Cover; cook on low heat setting for six to eight hours. Makes 16 servings. Back