Cook the egg in boiling water for about 8 minutes. Rinse with cold water and remove the shell. Chop the egg. Clean and wash the radishes and cut 2 pieces into sticks. Cut the remaining radishes in half.
Season yoghurt with salt and pepper. Carefully fold in egg and radish sticks. Cut the cress from the bed and fold in as well. Cut open the bread roll. Spread yoghurt cream on top and bottom.
Cover the lower halves with 2 slices of Pommern Spiess skewer each and place the tops of the rolls on top. Add the remaining radishes.