Making the Béchamel:Into a pot, melt butter, add flour and whisk vigorously. Cook for a few minutes to cook out the raw flour flavor. Add in warm milk a little at a time, whisking all the while to prevent lumps. Once all the milk has been added, season with salt, pepper and nutmeg. Cook on low medium until the mixture has thickened, 5-10 minutes.Stir in Parmigiano and set aside while your prepare the other ingredients.
Sauté shallot in olive oil, add spinach, season with salt, pepper and nutmeg. Sauté for a few minutes until wilted. Set aside.
Boil pasta according to package instructions until just before al dente. Drain, rinse under cold water and layout on paper towels to dry.
Preheat the oven to 400F.
Into a 9×12 baking dish, add a layer of béchamel.
Lay a piece of lasagna sheet down onto a clean surface, smear with béchamel, add spinach, Hatfield ham, and mozzarella. Roll it up. Place into baking dish. Continue this process until you have used up all the pasta.
Top the rolls with more béchamel, grated Parmigiano Reggiano and mozzarella. Cover with aluminum foil and bake at 400F for 30 mins covered and 20 minutes uncovered or until the top in a nice golden brown. **You can turn the broiler on in the last few minutes for a nice crust on top.**