If your noodles need to be cooked, boil noodles in a pot of hot water according to the package instructions. If you're using oven-ready noodles that don't need to be cooked, skip the cooking process and go straight to layering your lasagna.
Preheat the oven to 375 degrees Fahrenheit.
Pour 1 cup of the meat sauce into the bottom of a large 13” x 9” casserole dish and spread it evenly over the bottom.
Add one layer of noodles (for me, this requires 4 noodles).
Spread ⅓ of the meat sauce over the noodles, followed by half of the ricotta cheese (I simply dollop large spoonfuls on) and ⅓ of the grated mozzarella cheese (as well as 1/3 of the parmesan if using).
Layer on a second layer of noodles over the first layer, followed by ⅓ of the sauce on top of the noodles, the rest of the ricotta and ⅓ of the grated mozzarella (and parmesan).
Add a third layer of noodles then spread the remaining sauce and sprinkle the rest of the cheese on top.
Cover the baking dish with aluminum foil, leaving it tented so that it doesn’t stick to the top layer of cheese.
Bake on the center rack of the preheated oven for 45 minutes. The foil prevents the top from getting too brown or over-cooking the top layer of noodles. Remove the foil and bake for 10 more minutes, or until the cheese is golden-brown.
Allow the lasagna to rest for at least 10 minutes before slicing and serving.