The combination of the waxy potatoes, the buttery saltiness of the anchovies and the bitterness of the Caspe olives makes for a complex, flavoursome salad.
Boil the potatoes, allow to cool and cut into 3cm pieces. Add the mayonnaise, chopped Caspe olives and chopped anchovies and mix well together. Season with coarsely ground black pepper. Refrigerate for an hour or so to allow the flavours to develop and serve.