Arrange a rack in the middle of the oven and heat to 375°F. Cook the pasta and sauce while the oven is heating.
Bring a large pot of heavily salted water to a boil over medium-high heat. Meanwhile, make the sauce.
See Quick & Easy Marinara Sauce; can be cooked while the oven is heating and pasta is cooking.
When the water is boiling, add the pasta and cook until just tender. While the pasta is cooking, make the ricotta filling.
Stir the ricotta, 1/4 cup of the Parmesan, and salt together in a small bowl; set aside.
When the pasta is ready, drain it in a colander or strainer.
Return the pasta to the now-empty pot. Add half of the sauce (about 3 cups) and stir until the pasta is well-coated. Add the meat, stirring to mix thoroughly. Taste and season with salt and pepper as needed.
Add the ricotta mixture to the pasta and fold it in, leaving big pockets of ricotta here and there.
Transfer half of the pasta mixture into a 9×13-inch baking dish and spread into an even layer. Evenly sprinkle with half of the mozzarella. Top with the remaining pasta in an even layer.
Pour the remaining sauce over the pasta and spread into an even layer. Sprinkle the surface evenly with the remaining mozzarella and remaining 1/4 cup Parmesan.
Bake uncovered until the edges are bubbling and the cheese is completely melted and browned in spots, about 30 minutes.
Remove the baking dish to a wire rack and let cool 15 minutes before serving.