Preheat the oven to 400°F (200°C). Line two large rimmed baking sheets with parchment paper and set aside.
In a large mixing bowl combine the ground turkey, panko (or GF panko or oats), grated Parmesan, shredded onion, eggs, Worcestershire sauce, Italian seasoning, garlic powder, salt, and black pepper.
Gently mix the ingredients by hand until evenly combined without compacting the mixture.
Use a 2-tablespoon scoop to portion the mixture, then gently roll each portion between your palms to form smooth, round meatballs. Place them on the prepared baking sheets, spacing them slightly apart.
Bake for 15 minutes, or until the meatballs are set and cooked through.
Turn the oven to broil and broil the meatballs 1–2 minutes until golden on top; broil one sheet at a time if necessary. Watch closely to prevent burning.
Remove from the oven. If desired, brush the meatballs with a little olive oil to make them glisten, then serve or cool as needed.
