Preheat oven to 375 degrees.
In a medium bowl mix together the ground chicken, egg, garlic, onion powder, Italian seasoning, salt, black pepper, Worcestershire sauce, grated cheese, breadcrumbs, and 1/4 cup of the spaghetti sauce.
Form into 18 meatballs and place onto a baking sheet coated with cooking spray. I lay the foil on the sheet to help with clean-up.
Bake for 20 minutes.
As the meatballs are cook, cover the bottom of a 9 x 13 baking dish with 1/2 cup of the spaghetti sauce. After the meatballs are done place them in the baking dish. Pour the rest of the spaghetti sauce, and sprinkle the mozzarella cheese, over the top of the meatballs.
Cover the dish with foil and bake for another 20 minutes.
Serve hot.