Gather and prep ingredients before you begin. Grate zucchini and press it through a strainer to remove moisture, ensuring the texture of the dish stays perfect. Preheat oven to 400F while you combine ingredients for the meatballs.
Lightly mix together until just combined — don’t overmix, or the meatballs may lose their tender bite. Roll meatballs into golf ball-sized balls and arrange them in a casserole dish.
Bake for 25–30 minutes or until cooked through, then drain moisture if necessary. Lay kale around meatballs, top with sauce and cheese, and bake again for 10–12 minutes until the cheese has fully melted.
For a golden finish, broil for 2–3 minutes until slightly crisp on top. Serve immediately and enjoy the rich, comforting layers of flavor and texture in every bite.