Baked Ziti

1 lb box ziti pasta, uncooked
1 onion, chopped
1 lb lean ground beef
2 (26 ounce) jars spaghetti sauce
1 cup ricotta cheese
1 cup Kraft Grated Three Cheese Blend (you can substitute Parmesan)
1 1/2 cups mozzarella cheese

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.
3. Add spaghetti sauce, and simmer 15 minutes.
4. Preheat the oven to 350 F.Butter a 9 X 13 inch baking dish
5. Layer as follows: 1/2 of the ziti, ricotta cheese, 1/2 sauce mixture, remaining ziti, mozzarella cheese and remaining sauce mixture.
6. Top with grated 3 cheese blend.
7. Bake for 25-30 minutes or until cheeses are melted.
8. Served with salad and rolls

I am cutting this recipe in half so that we're not eating pasta for a month!!! With half of the recipe I fed 6 adults and 1 baby.  Everyone enjoyed it!!!