1. Pulse together carrots, celery, onion and garlic in food processor until finely chopped.
2. In large bowl, mix together chopped vegetables, meat, tomatoes, beef broth, tomato paste, sugar, oregano, salt, black pepper and cayenne pepper until well combined.
3. Place meat and vegetable mixture in 5- to 5-1/2-quart slow cooker.
4. Cover slow cooker; cook on high heat for 5-1/2 hours, stirring halfway through cooking time if possible.
5. Stir in thawed peas and heavy cream. Cover and cook for another 30 minutes.
6. Cook pasta in a large pot of lightly salted boiling water following the package directions until the pasta is al dente, firm but tender. Drain well; return to pot.
7. Add half of meat sauce, about 6 cups, to the pasta in the pot; toss and serve with grated Parmesan cheese on the side, if desired. Reserve the remaining half of the sauce for future meals. Freeze the sauce, tightly covered, for up to 3 months. Makes 8 servings.