For the marinade, mix all the ingredients together and season to taste. Cut the onions into fine cubes or rings, the bell bell pepper into strips or small cubes and the radishes into slices. Slice the bread dumplings and place them decoratively on the plates, approximately in a circle. Top with onions, peppers and radishes and drizzle with the prepared marinade. Sprinkle with parsley or chives and garnish with boiled eggs if desired.