From my inbox.  This is great to fix and freeze for later also.

Baked Ziti
Ingredients

2 lb. ground beef 
1 large onion, chopped 
1 jar (4 lb. 3 oz.) Prego Fresh Mushroom Italian Sauce (7 1/2
cups)
1 box (16 oz.) tube-shaped pasta (ziti), cooked and drained 
3 cups shredded mozzarella cheese 
1/2 cup grated Parmesan cheese 

Directions

Cook beef and onion in sauce pot until browned. Pour off fat.
Stir in pasta sauce, ziti and 2 cups mozzarella cheese. Spoon
into 2 (12 1/2 x 8 1/2 x 2) disposable foil pans. Top with
remaining mozzarella and Parmesan. Bake at 350 degrees F. for 30
min. or until hot. Serves 12.

TIP: To freeze, prepare ziti but do not bake. Cover with foil and
freeze. Bake frozen ziti, uncovered, at 350 degrees F. for 1 hr.
or until hot. Or refrigerate 24 hr. to thaw. Bake thawed ziti,
uncovered, at 350 degrees F. for 45 min. or until hot.