01 - In a large bowl, combine ground turkey, breadcrumbs, Parmesan cheese, egg, garlic, parsley, oregano, salt, black pepper, and milk. Mix gently until just combined to avoid tough meatballs.
02 - Shape the mixture into 16 to 18 evenly sized meatballs.
03 - Heat 2 tablespoons of olive oil in a large skillet over medium heat. Add meatballs in batches and brown on all sides, about 5 minutes total. Remove and set aside; meatballs will finish cooking in the sauce.
04 - In the same skillet, heat 2 tablespoons olive oil. Add the chopped onion and cook until softened, about 4 minutes. Add garlic and sauté for an additional minute.
05 - Stir in crushed tomatoes, dried basil, oregano, sugar if using, salt, and black pepper. Bring mixture to a simmer.
06 - Carefully add browned meatballs to the simmering sauce. Cover and cook on low heat for 20 to 25 minutes until meatballs reach an internal temperature of 165°F (74°C).
07 - Adjust seasoning to taste and stir in fresh basil if desired. Serve hot with pasta, polenta, or crusty bread.