Cut the vanilla pod lengthwise and scrape out the pulp. Pour milk into a pot, add vanilla pulp, bring to the boil. Take it off the stove and let it simmer for a while. Stir in sauce thickener, bring to the boil again. Sprinkle sugar over the sauce and cover with foil to prevent skin formation. Let it cool down.
Whip the cream until stiff. Carefully fold in horseradish. Arrange 3 slices of roast beef garnished with some salad and parsley on 4 plates. Add a dash of horseradish cream and sprinkle with pink berries. Ciabatta bread tastes good with it