This is how I make baked ziti - been making it this way for years
1 box of ziti, cook following package instructions
1 large jar of your favorite marinara
1/2 c sour cream
2 c shredded moz cheese
1/2 lb hamburger
1 -2 italian sausage links
1 onion chopped
1 garlic clove minced
Preheat oven to 375. Cook ziti according to package instructions. Meanwhile, brown hamburger and sausages with onions and garlic, drain grease. Add marinara sauce and simmer over low heat for 5-10 minutes.
drain ziti. Spray deep casserole dish with Pam spray. Put about 1 cup sauce in the bottom of the casserole dish, put half of the ziti in the pan. Next spread all of the sour cream and half of the mozerella over.
Next place half of the remaining sauce over the cheese. Next top with all of the remaining ziti, followed by all of the sauce. Top with remaining cheese.
Sprinkle with parmesan cheese and a few bits of fresh basil.
cover and bake for 30 minutes or until cheese is bubbly.