Prepare the Meat Sauce: In a large pot, brown the ground beef and sausage over medium heat. Drain off excess fat. Add the onion and cook until soft, about 5 minutes. Add the garlic and cook for 1 minute more. Stir in crushed tomatoes, tomato sauce, red wine (if using), oregano, basil, salt, and pepper. Bring to a simmer, then reduce heat to low, cover, and cook for at least 1 hour, stirring occasionally. This slow cooking develops the rich flavor.
Prepare the Cheese Filling: In a medium bowl, combine the ricotta cheese, beaten egg, 1/4 cup Parmesan cheese, parsley, and nutmeg. Mix well until fully combined. Set aside.
Cook Noodles: If using traditional lasagna noodles, cook them according to package directions until al dente. Drain and lay flat on parchment paper to prevent sticking. If using oven-ready noodles, skip this step.
Assemble the Lasagna: Preheat your oven to 375 degrees Fahrenheit. Lightly grease a 9×13 inch baking dish. Spread a thin layer of meat sauce on the bottom of the dish.
Layer 1: Arrange a layer of noodles over the sauce. Spread half of the ricotta mixture evenly over the noodles. Top with half of the sliced provolone cheese.
Bake: Cover the baking dish tightly with aluminum foil. Bake for 30 minutes. Remove the foil and bake for another 15-20 minutes, or until the cheese is bubbly and lightly browned.
Rest: Let the lasagna rest on the counter for 15 minutes before slicing and serving. This allows the layers to set properly.
Notes
Using whole milk dairy products contributes significantly to the richness and creamy texture of this decadent lasagna recipe.
For an even deeper meat flavor, substitute half of the ground beef with ground veal.
If you prefer a thicker sauce, allow the meat sauce to simmer uncovered for the last 20 minutes of cooking time.