Slow Cooker Short Rib Sauce

Name: Slow Cooker Short Rib Sauce
Prep time: 15 min
Cook time: 4 h
Total time: 4 h
Yield: 8
Ingredients: Ingredients; 2 tablespoons extra virgin olive oil; ½ yellow onion, small diced; 2 carrots, peeled and small diced; 4 garlic cloves, peeled and minced; 1 cup dry red wine; ¼ cup tomato paste; 15 oz. can crushed tomatoes; 1 (2”) piece parmesan rind (optional); 1 teaspoon dried thyme; 1 bay leaf; 1 tablespoon white sugar; 1 tablespoon salt; 1 teaspoon ground black pepper; 2½ pounds bone-in short ribs; Grated parmesan cheese