Bring a large pot of salted water to a boil. Add ziti pasta, and cook until al dente according to package directions, about 8 minutes; drain.
In a large skillet, brown onion and sausage (or beef ) over medium heat. Drain the fat. Add minced garlic and cook for a minute or so. Add the marinara sauce and Italian seasonings to the cooked sausage, and simmer 15 minutes.
Preheat the oven to 350 degrees. Butter a 9x13 inch baking dish. Layer as follows: 1/2 of the ziti, 1/2 meat sauce mixture, all of the Provolone cheese, all of the sour cream, remaining ziti, remaining sauce mixture and then mozzarella cheese. Top with grated Parmesan cheese.
Spray aluminum foil with cooking spray so it doesn't stick to the cheese. Bake for 20 minutes in the preheated oven. Remove the foil and bake for an additional 10-15 minutes or until the cheese is melted and starts to brown. Top with fresh basil if desired.
Notes
FREEZER INSTRUCTIONS:
Prepare up to step 3 before baking. Wrap tightly with plastic wrap and freeze unbaked casserole up to a month.The night before using, pull from the freezer and thaw in the fridge overnight. To bake, cook covered with foil for 30 minutes at 350 degrees. Uncover and bake another 15-20 minutes or until the cheese is melted and bubbly.