Make a quick panade: In a large bowl, stir together the breadcrumbs and milk.
Let it sit for 2 minutes until softened.
Add aromatics and seasonings: Mix in the egg, Parmesan, garlic, onion, parsley, basil, Italian seasoning, red pepper flakes, salt, and black pepper until combined.
Fold in the turkey: Add the ground turkey and gently mix with a fork or your hands just until everything is evenly distributed. Don’t overwork the mixture—it can make the meatballs tough.
Shape the meatballs: With damp hands or a small scoop, form 1.5-inch balls (about 18–22 meatballs). Place them on a parchment-lined sheet.
Option A—Pan-sear and simmer: Heat olive oil in a large skillet over medium heat. Sear the meatballs in batches, turning to brown on all sides, about 5–7 minutes total.
Pour in marinara, bring to a gentle simmer, cover, and cook for 10–12 minutes until cooked through (165°F/74°C).
Option B—Bake: Preheat oven to 400°F (200°C). Arrange meatballs on a greased or lined baking sheet. Bake for 15–18 minutes, or until the centers reach 165°F.
Warm marinara separately and spoon over to serve, or simmer the baked meatballs in sauce for 5 minutes for extra flavor.
Taste and finish: Adjust salt in the sauce if needed. Garnish with extra Parmesan and chopped basil or parsley.