Mix everything except the mozzarella & tomato sauce together. Roll mixture into 8 balls. Push one 1" cube of mozzarella into the center of each ball. Pour tomato sauce into saute pan, add meatballs, cover and cook for 15 minutes on med-high heat. Roll occasionally.
The cheese in the center will melt and the oil will make the meatballs VERY moist and juicy. Also, the problem of a raw center is gone and the meatballs cook quicker than with out the cheese center. Serve with pasta and your choice of red sauce.