A lady I worked with brought this in one day, and it was a hit. Now it is the favorite of all my dinner guests. It's great for a covered dish dinner too. I have made this also without the meat, and it is well received.

Ingredients 

55 m   -   10 servings   -  578  cals 

• 1 pound dry ziti pasta 
• 1 onion, chopped 
• 1 pound lean ground beef 
• 2 (26 ounce) jars spaghetti sauce 

• 6 ounces provolone cheese, sliced 
• 1 1/2 cups sour cream 
• 6 ounces mozzarella cheese, shredded 
• 2 tablespoons grated Parmesan cheese 

Directions 

Prep : 20  m  - Cook : 35  m  - Ready In : 55  m

1. Bring a large pot of lightly salted water to a boil. Add ziti pasta, and cook until al dente, about 8 minutes; drain.                              
2. In a large skillet, brown onion and ground beef over medium heat. Add spaghetti sauce, and simmer 15 minutes.  
3. Preheat the oven to 350 degrees F (175 degrees C). Butter a 9x13 inch baking dish. Layer as follows: 1/2 of the ziti, Provolone cheese, sour cream, 1/2 sauce mixture, remaining ziti, mozzarella cheese and remaining sauce mixture. Top with grated Parmesan cheese.  
4. Bake for 30 minutes in the preheated oven, or until cheeses are melted. 

Source : allrecipes.com