In a large mixing bowl, combine ground beef, breadcrumbs, grated Parmesan cheese, egg, garlic powder, Italian seasoning, salt, and pepper. Mix thoroughly until everything is well blended, being careful not to overwork the meat. Roll the mixture into small meatballs, about 1 inch in diameter, and set them aside on a plate while you prepare the soup.

In a large pot over medium heat, add a drizzle of olive oil. Once hot, add diced onion, chopped carrots, and celery. Sauté for about 5 to 7 minutes until the vegetables become tender and the onion is translucent.

Carefully add the meatballs to the pot, cooking them for about 5 minutes until they are browned on all sides. Remove the meatballs and set them aside on a plate.

In the same pot, pour in the vegetable broth and add the diced tomatoes, stirring well to combine. Bring the mixture to a gentle simmer over medium-high heat.

Once the broth is simmering, carefully return the browned meatballs to the pot. Stir in the heavy cream, mixing until well combined. Allow the soup to simmer for another 10 minutes.

Remove the pot from heat and give the soup a final stir. Serve hot, garnishing each bowl with fresh basil and Parmesan shavings.