I think this should be renamed "The Best Baked Ziti I Ever Had." It really is, too! I've made this several times and it nevers lasts long enough to get a good picture. These pics do not do it justice, but trust me when I say it is delicious. It's not the traditional baked ziti either. It uses sour cream in place of ricotta cheese which I like way better. It also has a layer of provolone in it. I could have used more Parmesan Cheese for the top but ran out. I also found from making it before that fresh shredded Parmesan is much better to use than the grated version. If you like Italian food I really do urge you to try this. I think you will enjoy it. Once again, courtesy of Allrecipes.
Bring a large pot of lightly salted water to a boil. Add ziti pasta and cook according to package directions; drain.
In a large skillet, brown onion and ground beef over medium heat. Drain excess fat. Add spaghetti sauce and simmer about 15 minutes.Preheat oven to 350 degrees F. Butter (I used olive oil cooking spray) a 9 x 13 inch baking dish. I also add a little of the sauce mixture to the bottom of the dish to prevent sticking. Layer as follows: 1/2 of the ziti, Provolone cheese, sour cream, 1/2 of sauce mixture, remaining ziti, mozzarella cheese and remaining sauce mixture. Top with Parmesan cheese.
Cover with foil and bake for 30 minutes in preheated oven on top of baking sheet. Remove foil and bake an additional 10 minutes.
This tastes much better the second day so if you decide to heat this up the next day after it's been in the fridge than bake approximately 45 minutes to 1 hour covered and 10 minutes more uncovered.