Melt butter in a large pot over medium-high heat.
Sauté diced onion and garlic until tender, about 5 minutes.
Pour the beef stock into the pot.
Add tomatoes, green beans, carrot, kale, Italian seasoning and bay leaf. Bring the mixture to a boil.
Reduce heat and stir in Cooked Perfect meatballs and tortellini.
Simmer on medium for 5 minutes.
Serve in bowls with Parmesan cheese.