• Preheat oven to 375ºF (190ºC). If you haven't already done so, grate the onion, mince the garlic, and grate the cheese.

Make The Tomato Meat Sauce

• Place a 5 or 6-quart (4.73 L or 5.68 L) cast iron Dutch oven on the stovetop over medium-high heat. Add the olive oil. Once the oil is hot, add the ground beef and sausage in a single layer to brown without stirring. Once the meats are almost cooked, stir and break them into smaller pieces.
• Add the grated onion and minced garlic (3 cloves) to the meats. Cook until fragrant, about 2 to 3 minutes. Stir in the crushed tomatoes, fennel seeds, salt, and pepper. Reduce the heat to medium-low and simmer for 20 minutes.

Make The Cheese Layers

• While the sauce simmers, make the cottage cheese layer. Whisk the egg, Italian seasoning, minced garlic, salt, and pepper. Stir in the cottage cheese.
• In another bowl, mix the mozzarella and Parmesan cheese.

Assemble The Lasagna

• To assemble the lasagna, ladle ¾ of the sauce out of the Dutch oven and into a bowl. Add a layer of noodles to the base layer of sauce left in the pot. Top the noodles with another quarter of the sauce, half of the cottage cheese mixture, and a third of the mozzarella mixture. Repeat with a layer of noodles, a quarter of the sauce, the remaining half of cottage cheese, and a third of the mozzarella mixture. Finish with a layer of noodles, the last of the sauce, and the last of the mozzarella mixture.
• Cover the Dutch oven with the lid and bake the lasagna for 45 minutes. Remove the lid, set the oven to broil, and continue to bake the lasagna until the cheese bubbles and browns, about 4 to 5 minutes more. Cool for 10 minutes before serving with more Parmesan cheese.