Cheese Stuffed Meatballs

MI've always loved pasta, it's one of my favourite things to eat which is not very good when you're trying to lose weight but oh well, I would NEVER not eat it, I love it too much. Anyway as I was looking through one of my new cookbooks I found this yummy recipe and had to try it. This was a hit with everyone, my only problem was that I think I should have cooked the meatballs a little longer in the oven and in the pan afterwards but we were in a rush and the pasta was cooked. They were fully cooked but I think they could have been more firm, maybe adding more bread crumbs would have helped with that too, I'll try that next time.
4 sticks mozzarella string cheese, cut into 18 cubes
1/2 c. Italian style bread crumbs
1 jar (48 oz.) tomato pasta sauce
1 1/2 lbs. lean ground beef
2 T. finely chopped onion
1/2 tsp. salt
1/2 tsp. dried oregano leaves
1 egg
Pasta (how ever much feeds your family normally and whatever type you like)
2/3 shredded parmesan cheese (or whatever cheese you like)

***Place cheese cubes in a baggie and freeze for at least 1 hour before making this recipe***
Heat oven to 375F. Line a 10x15x1 baking dish with foil and spray with cooking spray. In a large bowl mix bread crumbs and 3 T. of the pasta sauce. Next stir in beef, onions, salt, oregano and egg. I used my hands for this, it just made it a lot easier. Shape mixture into 18 (2-inch) balls. Press 1 cheese cube into each ball, sealing it inside. Place each meatball into baking dish carefully. Bake for 10 minutes. Meanwhile pour remaining pasta sauce into a large pot (it said to use a dutch oven but I don't have one) and simmer over med-high heat, stirring frequently. Once meatballs are cooked, add them to the pasta sauce in the pot and reduce heat to med-low. Cover and simmer for 10 minutes, stirring occasionally until meatballs are thoroughly cooked and no longer pink. Serve with any kind of pasta you like. Serve with cheese if you like and ENJOY :) Anything with cheese is great with me and my family, I think that's why I wanted to try this recipe.