Step 1: Prepare the Meat Sauce

1. Heat olive oil in a large pan over medium heat. Add onion, garlic, carrot, and celery. Sauté until soft.
2. Add the ground beef, salt, pepper, oregano, and basil. Cook until browned, breaking up the meat with a spoon.
3. Stir in tomato paste and cook for 1 minute. Add crushed tomatoes, wine (if using), beef broth, and bay leaf.
4. Simmer uncovered for at least 30–45 minutes, stirring occasionally. Remove bay leaf before assembling the lasagne.

Step 2: Make the Béchamel Sauce

1. In a saucepan, melt butter over medium heat. Stir in flour and cook for 1 minute, whisking constantly.
2. Gradually add warm milk while whisking to prevent lumps. Cook until thickened.
3. Season with salt and nutmeg. Set aside.

Step 3: Assemble the Lasagne

1. Preheat oven to 375°F (190°C). Grease a 9×13-inch baking dish.
2. Spread a thin layer of meat sauce on the bottom of the dish.
3. Add a layer of lasagne noodles, then spread some ricotta mixture, followed by meat sauce and béchamel.
4. Repeat layers, finishing with a generous amount of mozzarella and Parmesan on top.

Step 4: Bake and Serve

1. Cover with foil and bake for 30 minutes.
2. Remove foil and bake for an additional 15–20 minutes, until the top is golden and bubbly.
3. Let lasagne rest for 10–15 minutes before slicing and serving.