In a large skillet over medium heat, warm 2 tablespoons of extra-virgin olive oil, adding 5 ounces of pancetta. Sauté until browned, approximately 4 minutes. Next, incorporate 1 pound of hot Italian sausage and 1 pound of ground beef, breaking apart as they cook until browned. Once browned, stir in 6 cloves of minced garlic and 1 cup of chopped onion, cooking until softened, about 5 minutes. Then mix in 3 tablespoons of tomato paste, 1 cup of dry red wine, and ½ cup of beef stock. Finally, add 2 cans of crushed tomatoes, season with salt, pepper, and sugar, and let the mixture simmer for 40 minutes on low heat.

In a medium bowl, combine 16 ounces of ricotta cheese, 5 ounces of grated fontina cheese, 1 large egg, and 1 egg yolk. Sprinkle in ¼ teaspoon of ground nutmeg for added warmth, and mix everything together until smooth and well blended.

Bring a large pot of salted water to a boil, cooking 15 lasagna noodles according to package instructions for about 4 minutes until al dente. Once cooked, gently drain the noodles and lay them on a sheet of parchment paper to cool.

Preheat your oven to 375°F (190°C). Grease a 9x13-inch baking dish with a touch of olive oil. Start layering by spreading a thin layer of meat sauce on the bottom, followed by three lasagna noodles. Next, add a portion of the ricotta mixture and another layer of meat sauce. Repeat this layering process until finished, ensuring the last layer is topped with 8 ounces of shredded mozzarella cheese.

Cover the assembled lasagna loosely with aluminum foil and place it in the preheated oven. Bake for 30 minutes, then remove the foil and bake for an additional 15-20 minutes.

Once baked, remove the lasagna from the oven and let it rest for at least 15 minutes.