Preheat the oven to 400°F and line a sheet pan with parchment.

Gently combine the chicken, parmesan, grated onion, garlic, egg, Italian seasoning, salt, and pepper — stop the moment it comes together.

Roll into 20 meatballs with wet hands and space them on the pan.

Bake 16 to 18 minutes, until the centers hit 165°F.

Warm the marinara in a large skillet, add the baked meatballs, and turn to coat for a minute or two.

Finish with basil and serve over pasta, zucchini noodles, or with good bread.