Par-cook the Italian sausage. If you choose ground sausage, crumble it as you go. If you prefer sausage links, slice them into rings after you remove them from the pan. (I prefer links!) Let the sausage drain on a paper towel for a few minutes.

While you cook the sausage, boil a large stockpot of water, seasoned with salt. Cook the entire box of ziti until al dente. Drain it in a colander.

Preheat your oven to 350° while the pasta cooks.

Grab your favorite large casserole bowl. Drizzle the olive oil into the pan, and coat the surface so that the pasta will not stick. I.e., you will find it far easer to clean up later. Plus, it adds a nice flavor!

Put the drained pasta, the jar of marinara sauce, and half of the mozzarella cheese into the casserole; stir to combine. Layer the sausage evenly across the top of pasta--the ziti will absorb the delicious juices that will weep from the sausage.

Cover the casserole with the lid or aluminum foil. Bake for 25 minutes.

Top with the other half of mozzarella and the parmesan. Return to the oven, uncovered, and turn the oven to "broil" for about three minutes. (Don't take your eye off this, it can go from brown to burnt in a matter of seconds). Remove the baked ziti when the cheese has a slightly golden brown color.