Baked Ziti

1 lb ziti pasta, cooked al dente
1 lb HOT Italian sausage, cooked and chopped
1 package of button mushrooms, sliced
1 (15 oz) container ricotta cheese
2 tbsp parsley
1 egg
1/4 cup Parmesan cheese
4 cups mozzarella cheese, shredded
1 (28 oz) jar pasta sauce

Cook ziti according to package directions, drain, and set aside. Mix ricotta, egg, parsley, 2 cups mozzarella, and Parmesan in a large bowl. Mix cooked sausage and pasta in ricotta mixture. Mix in 3/4 jar of sauce. Transfer to casserole dishes. Top with the rest of the sauce and mozzarella cheese. Bake for 30-45 minutes, or until hot and bubbly. If freezing, prepare and freeze before baking. Thaw out and bake according to directions.