01 - In a large mixing bowl, thoroughly combine the cooked ziti pasta, Italian sausage, marinara sauce, and ricotta cheese. Season the mixture with salt and freshly ground black pepper according to taste.
02 - Transfer the prepared pasta mixture into a greased baking dish, ensuring even distribution. Sprinkle the shredded mozzarella cheese uniformly over the top.
03 - Place the baking dish in a preheated oven at 375°F and bake for 25 to 30 minutes, or until the surface is golden and the cheese is bubbling.
04 - Allow the baked ziti to rest for 5 minutes before serving to set. Portion and enjoy.