Preheat your oven to 350°F and lightly grease a 9x13 inch baking dish with cooking spray or butter. Finely dice the yellow onion into 1/4-inch pieces and mince the 4 garlic cloves. This prep work ensures everything is ready when you need it, preventing any rushed moments during the cooking process.

In a large skillet over medium-high heat, brown the ground beef and Italian sausage, breaking them into small pieces as they cook—this takes about 8-10 minutes. Once the meat is cooked through, drain off excess fat, then add the diced onion and cook for 2-3 minutes until softened. Add the minced garlic and red pepper flakes, stirring constantly for about 30 seconds to release their aromatics. Pour in the marinara sauce and stir in the oregano, salt, and black pepper. Reduce heat to low and let the sauce simmer gently while you prepare the other components—this allows the flavors to meld beautifully.

Bring a large pot of salted water to a boil and cook the lasagna noodles for 2 minutes less than the package instructions—this keeps them slightly under al dente so they won't become mushy in the oven. Drain and lay them flat on parchment paper to prevent sticking. While the noodles cook, combine the cottage cheese, egg, freshly grated Parmesan, parsley, salt, black pepper, and grated nutmeg in a bowl, stirring until well combined. I like to use Daisy brand cottage cheese for its thick consistency—it holds together better than watery brands and creates a creamy layer without excess moisture.

Spread a thin layer of the meat sauce from Step 2 on the bottom of your prepared baking dish. Arrange 4 noodles over the sauce in a single layer, overlapping slightly if needed. Spread half of the mozzarella and Swiss cheese mixture over the noodles, then top with 4 more noodles. Spread half of the remaining meat sauce over these noodles. Add the cottage cheese mixture from Step 3 in an even layer, then top with the final 4 noodles. Pour the remaining meat sauce over the top, and finish by sprinkling the remaining mozzarella and Swiss cheese evenly over the surface. I find that mixing mozzarella and Swiss together creates a more complex cheese flavor than using mozzarella alone.

Cover the baking dish with foil and bake at 350°F for 35-40 minutes until the lasagna is heated through and the cheese on top is beginning to bubble at the edges. Remove the foil for the last 5 minutes if you prefer a more golden top. Let the lasagna rest for 10 minutes before slicing—this resting period allows the layers to set so each serving holds together cleanly instead of falling apart on the plate.