Florentine Stuffed Chicken

1 (10 ounce) package frozen chopped spinach, thawed and drained

¼ cup grated Parmesan cheese

½ cup chopped onion

4 bone-in chicken breast halves, with skin

2 cups spaghetti sauce

¼ cup shredded mozzarella cheese

Preheat oven to 350 degrees F (175 degrees C).

In a medium bowl, combine the spinach, Parmesan cheese and onion and mix thoroughly. Stuff the cavity of each chicken breast with 1/4 of the mixture. (NOTE: Bone-in split breasts usually have a little cavity; if one is not naturally present, use a sharp knife to make a slit in the side of the breast.)

Lay stuffed breasts in a 9x13 inch baking dish, and cover with the sauce.

Bake at 350 degrees F (175 degrees C) for about 35 minutes, or until chicken is cooked through and tender; sprinkle with mozzarella cheese and bake another 5 minutes, until cheese is melted.