Preparing the bolognese sauce:

• Dice the celery, onion, and carrot. Mince the garlic.
• In a large skillet, heat some olive oil and begin sautéing the celery, onion, and carrot until the onion becomes translucent. Season with salt and pepper.
• Add the garlic and bay leaves, and sauté for another 2 minutes.
• Increase the heat, add the ground beef and chopped bacon, and cook until browned.
• Pour in the white wine and let it reduce.
• Add the peeled tomatoes, crush them to avoid large chunks, mix well, cover, and simmer on low heat for about 10 minutes.

Making the bechamel sauce:

• In a saucepan, melt the butter and wait until it starts to foam. Stir in the flour and cook until it forms a light golden paste.
• Gradually add cold milk, continuously stirring to prevent lumps. Cook for an additional 3 minutes after all milk has been added, ensuring the sauce is creamy but not too thick or thin. Adjust the thickness by adding milk gradually.
• Season with freshly ground nutmeg, salt, and pepper to taste.

Assembling the lasagna:

• In a baking dish, start with a layer of both sauces to create a base. Lay down the first layer of fresh lasagna noodles.
• Add more sauce and Bolognese on top of the noodles, followed by slices of mozzarella cheese.
• Repeat layering noodles, sauces, and cheese until all ingredients are used, finishing with a layer of Bolognese and mozzarella.
• Generously top with freshly grated Parmesan cheese for a golden crust.

Baking:

• Bake in a preheated oven at 375°F for about 20 minutes if using fresh pasta (or 40 minutes if using other types of pasta). For a golden top, turn on the broiler in the last few minutes of baking.