I haven't actually made this - I saw it on an old episode of "Oliver's Twist" and I loved the idea. Don't want to forget it, so I thought I'd post it!
Quick tomato sauce:
1 onion, chopped
2 cloves garlic, minced
2 cans crushed tomatoes (I'm guessing he used the smaller cans, not the 28 ounce).
1 handful fresh basil
Saute the onion in some olive oil until soft. Add garlic and cook until you can smell it (careful not to burn it!). Add tomatoes and simmer for 15 minutes. Stir in fresh basil and let it wilt.
For the casserole:
1 batch Italian-style meatballs (use your favorite recipe)
sliced fresh mozzarella
shredded parmesan cheese
Spoon the tomato sauce into the bottom of a medium-size casserole dish. Cover the sauce with meatballs, then top with sliced fresh mozzarella and sprinkle with parmesan.
Bake at 350 degrees until cheese is bubbly and meatballs are cooked through. Serve with pasta on the side.