Preheat the oven to 375°F (190°C).

Bring a large pot of salted water to a boil. Add lasagna noodles and cook until al dente per package directions. Drain and lay flat to prevent sticking.

In a large skillet over medium heat, cook ground beef and Italian sausage, breaking up the meat, until browned and cooked through. Drain excess fat and season with salt and pepper.

In a medium bowl, stir together ricotta, the egg, oregano, basil, and a pinch of salt and pepper until smooth.

Spread about 1 cup of marinara sauce on the bottom of a 9×13-inch baking dish.

Arrange 4 lasagna noodles over the sauce in a single layer. Spread half the ricotta mixture evenly over the noodles. Spoon half the meat mixture over the ricotta, then add a layer of marinara and sprinkle with 1 1/3 cups mozzarella.

Repeat with another layer: noodles, remaining ricotta, remaining meat, more sauce, and another 1 1/3 cups mozzarella.

Finish with a final layer of noodles, the remaining marinara sauce, the remaining mozzarella, and a generous sprinkle of Parmesan.

Cover the dish tightly with aluminum foil and bake for 25 minutes. Remove the foil and bake an additional 25 minutes, until the cheese is bubbly and golden.

Let the lasagna rest for 15 minutes before cutting to allow the layers to set.