Cut the cooked beetroot into slices a good 1/2 cm thick. Mix a vinaigrette from oil, vinegar, salt, pepper and basil. Turn the beetroot slices in it and arrange them decoratively on a platter.
For the horseradish cream, mix the cream cheese with milk, possibly a little salt and enough grated horseradish to create a tangy, piquant, but not too hot mixture. Fill this into a piping bag or a pastry syringe with a large star nozzle and squirt a thick tuff onto each beetroot thaler. Decorate each with a walnut half and stick a toothpick through it if you like.