Step 1

Bring a pot of salted water to the boil and add the potatoes. Cook until soft, then drain and leave to cool. When cool, put in a bowl with the spring onions, apple, horseradish and anchovies and fold all of the ingredients gently together.

Step 2

Separate the egg yolk from the egg white and finely chop both.

Step 3

To assemble the salad, put a layer of the lettuce at the bottom of a large glass bowl. Top the lettuce with a layer of potato salad (reserve a little potato salad), followed by a layer of carrots, beetroot, cucumber and a final layer of potato salad. As you are building up the layers, sprinkle the dill and cornichons throughout each layer and season with a little salt and pepper.

Step 4

Top the salad with the chopped egg and a final sprinkling of dill.