Heat the milk. In a saucepan melt the butter, remove from the heat and add the flour all at once, stirring vigorously with a whisk to prevent lumps from forming.
Put back on the heat, stirring constantly for a few moments. Add a little milk, dilute well with a whisk and finally add the rest of the milk, stirring constantly.
Let cook over low heat until the sauce has thickened, about 5 minutes. Just before turning off, add a little salt and nutmeg.
Clean the radicchio, cut it into strips and let them cook in a pan covered with a drizzle of oil. Salt, take one half, chop it and put it again into the pan.
Butter a Lasagna pan. Arrange a veil of bechamel, a layer of Lasagna sheets, followed by the radicchio, a few slices of scamorza and the bechamel. Continue until all the ingredients are finished. Finish with a generous sprinkling of Parmesan cheese and a few flakes of butter.
Bake at 180 degrees for 30 minutes.
Remove from the oven your Lasagna, let stand 5 minutes before serving.