1 Cut the potatoes, beetroot, peeled onion, apples and gherkin into very small pieces and mix with the mayonnaise, lemon juice, vinegar, salt and pepper. Taste and adjust the seasoning.
2 Place the ring of the springform pan on a large plate. Take a little of the beetroot and potato mixture and spread on the plate inside the springform ring. Arrange the Skorpa rolls side by side around the ring, with the rounded sides towards the ring, and fill the middle with the rest of the vegetable mixture.
3 To garnish, remove the springform ring, tie a ribbon around the charlotte and decorate with olives and pearl onions.