Mix the Meatballs: In a large bowl, mix together ground beef, egg, Parmesan cheese, garlic powder, onion powder, Italian seasoning, salt and pepper. Stir until combined and shape into soft balls.
Brown the Meatballs: In a large pot, heat olive oil and brown the meatballs very well on all sides but do not cook completely. Remove and set aside.
Prepare the Broth: Melt butter in same pot, add beef broth and diced tomatoes (if using). Once all of the ingredients are combined bring the mixture to a simmer – that’s where the magic happens.
Combine Ingredients: Place the browned meatballs and diced spinach or kale into the pot with the simmering broth. Cook for 15 – 20 minutes or until the meatballs are cooked and tender.
Serve Warm: Serve the warm Keto Meatball Soup in bowls, top with additional Parmesan and enjoy supper that’s also low carbohydrate.