For the béchamel, pour the milk into a small saucepan, add nutmeg and salt, and heat gently.

In another small saucepan, melt the butter over low heat.

Add the flour and whisk to prevent lumps from forming.

When the flour turns golden, gradually add the milk, first a little at a time, then all at once.

Stir over low heat until the sauce thickens to your desired consistency.

Meanwhile, cut the broccoli into pieces and bring a pot of water to a boil.

Salt the water, add the broccoli, and boil for a few minutes. The broccoli is ready when a fork easily pierces it.

Drain the broccoli, add it to the béchamel, and blend with an immersion blender until smooth.

Bring a pot of water to a boil for the pasta and cook the pasta until al dente, then drain.

Combine the pasta with the broccoli béchamel, diced pancetta, and mozzarella cut into pieces in a baking dish. Sprinkle generously with grated cheese.

Bake in a convection oven at 350°F (180°C) for 10 minutes, then broil for 5 minutes to create a golden crust.