Hard boil the egg, quench under cold water and let it cool down. Wash the cucumber, dab dry and slice into thin slices. Arrange cucumber slices on 4 plates. Peel onion and chop finely. Wash and halve the tomato and remove the seeds. Cut tomato halves into small cubes.
Wash the dill, shake dry and cut finely except for a little to garnish. Mix vinegar, onion, some salt and pepper, then add oil. Peel and chop the egg and add it to the vinaigrette together with the tomatoes, capers and half of the dill. Spread the vinaigrette over the cucumber slices. Sprinkle with remaining dill and garnish
Waiting time 10 minutes