Step 1

Boil the potatoes for 10-12 mins until tender. Drain thoroughly, then roughly mash.

Step 2

Mix the potato, spring onions, parsley and fish. Season with a little black pepper, then shape into 4 fish cakes. Dip each in the egg and then breadcrumbs to cover. Chill for at least 10 mins.

Step 3

Whizz the mayo with a small handful of watercress. Season and stir through the capers. Heat a thin layer of oil in a frying pan. Fry the fish cakes for 1 min on a high heat until crisp and brown, then cook for about 4 mins on a lower heat. Repeat on the other side, ensuring the fish is cooked all the way through. Serve with the remaining watercress and the mayo. (See tips on freezing, below left.)