In a large bowl, combine the ground beef, garlic powder, onion granules, parsley, egg, milk, breadcrumbs, nutmeg, allspice, salt, and pepper.

Mix it all together with your hands until it's well combined.

Shape the mixture into small meatballs, about 1 inch in diameter.

Heat the olive oil in a large pot or Dutch oven and fry the meatballs in batches until browned. Set the meatballs aside.

In the same pot, melt the butter then add the diced onion, carrots, and celery. Cook for 5-6 minutes or until the vegetables soften.

Stir in the garlic and cook for another minute until fragrant.

Next, stir in the Worcestershire sauce and Dijon mustard, then pour in the beef stock and bring to a simmer.

Add the pasta and cook for 10-12 minutes or until al dente. Stir in from time to time to prevent the pasta from sticking to the bottom of the pot.

Transfer the cooked meatballs to the pot and simmer for 1-2 minutes until heated through.

Take ¼ cup of liquid out of the soup and mix it with the sour cream to temper it. Add the mixture to the pot and stir well to combine.

Season with salt and freshly ground black pepper to taste and garnish with fresh parsley. Serve hot, sprinkled with an extra crack of black pepper and chopped parsley if you like.