If you have a food processor, chopping the vegetables is a breeze! Add carrots, celery, red onion, and garlic in a food processor and pulse until vegetables are minced, stopping to scrape down sides when necessary.
In a large Dutch oven or stock pot, melt the butter with the olive oil over medium heat and add the chopped vegetables. Lightly salt and pepper and saute for about 5 minutes, until tender.
Sprinkle the ground beef lightly with garlic salt and pepper. Add to Dutch oven along with the Italian sausage. Use a wooden spoon or potato masher to grind up the meat as it cooks.
Once the meat is cooked through, add tomatoes, consomme, salt and pepper, and sugar. Cook over medium heat, stirring occasionally, for about 30 minutes.
Then add cream into meat sauce and simmer for about 1 hour longer, stirring occasionally.
After simmering for an hour, add in the lemon zest and parmesan cheese. Stir well until cheese has melted into the sauce. Serve with a wide noodle pasta or freshly made gnocchi with additional parmesan. Or use as meat sauce in your lasagne. Mangia!