In a large bowl, gently combine ground beef, veal, pork, breadcrumbs, eggs, Parmesan, garlic, parsley, salt, and pepper.
Mix with your hands until just combined—avoid overworking the meat to keep meatballs tender.
Shape the mixture into 1½-inch meatballs, about 24 pieces. Place on a baking sheet.
Heat olive oil in a large skillet over medium heat. Add meatballs in batches, turning occasionally, until golden brown on all sides (about 8–10 minutes).
If desired, transfer browned meatballs to a pot of simmering marinara sauce. Cover and cook for an additional 15 minutes to infuse flavor.
Serve hot over pasta, in a sandwich, or as a tasty appetizer with fresh basil and extra Parmesan.