800g skin-on cod fillet
4 tbsp milk
I large celeriac, peeled
300g baking potatoes, peeled and cut into chunks
80g pack prosciutto crudo, chopped
2 tbsp capers
1 tbsp finely chopped thyme
1 medium British Blacktail Free Range Egg, beaten
Polenta or plain flour, for dusting
1 small clove garlic, crushed
100ml half-fat crème fraîche
100g half-fat mayonnaise
25g pack fresh fl at-leaf parsley, finely chopped
Vegetable oil, for shallow frying
Lemon wedges, to serve
140g pack Waitrose Wild Rocket, to serve

1. Put the cod in a frying pan with the milk. Cover and cook gently for about 10 minutes, or until cooked through. Leave to cool in the pan.

2. Meanwhile, cut the celeriac into chunks and place in a pan with the potatoes. Cover with cold water and bring to the boil. Reduce the heat to a gentle simmer and cook until tender, about 15-20 minutes. Drain thoroughly, return to the pan and mash until fairly smooth.

3. Remove the fish from the pan and flake into pieces, discarding the skin and checking for any bones. Add to the mash with the prosciutto, capers, thyme and a little seasoning. Drizzle with the egg and mix together. Divide the mixture into 12 pieces. Shape into chunky cakes about 2cm thick, dusting both sides with polenta or flour.

4. For the sauce, mix together the garlic, crème fraîche, mayonnaise and parsley and transfer to a small serving dish.

5. Heat a little oil in a frying pan and fry the fishcakes, in batches, for about 3 minutes on each side until golden. Keep warm while frying the remainder. Serve with the sauce, lemon wedges and salad leaves