Wash the potatoes and cook for about 25 minutes in boiling salted water. Drain potatoes, rinse and peel. Wash lemon, grate dry and grate the peel. Halve the lemon and squeeze. For the vinaigrette, mix 4 tablespoons of lemon juice and vinegar, fold in the oil. Season vinaigrette with a little sugar, salt and lemon pepper. Cut the potatoes into slices, mix with the vinaigrette and leave to stand for about 2 hours.
Clean, wash and drain the radicchio. Pluck leaves into bite-sized pieces. Wash parsley, dab dry and chop the leaves coarsely. Cut the avocado in half, remove the core and peel, or use a tablespoon to remove the skin. Cut avocado halves into slices. Season potato salad again with salt and lemon pepper and fold in radicchio, parsley and avocado just before serving. Garnish salad with pink pepper berries
Preparation time about 1 hour (waiting time about 2 hours)