Step 8: Finish the Layers - Add the remaining noodles, more meat sauce, the rest of the cheese mixture, and the remaining spinach. Make sure the noodles have enough sauce around them because that moisture is what cooks them in the oven. Finish with the sliced fresh mozzarella across the top. The dish will be full, and that is exactly right. Put the baking dish on a
rimmed sheet pan if you are worried about bubbling over. That little dad move saves you from cleaning the oven later.