Ingredients

Step by step

1. To make the mayonnaise, put the egg yolks, vinegar, mustard and seasoning in a blender and whiz until combined. Gradually add the oil, a few drops at a time. Once all the oil is incorporated and you have a thick glossy mayonnaise, add most of the watercress and blend until you have a beautiful green sauce; season well. Cover and chill until ready to serve. Reserve the rest of the watercress to garnish.
2. For the prawn cakes, mix the chilli, spring onions, dill and prawns with the mashed potato. Lightly beat one of the eggs and add to the mixture, along with some seasoning. Mix to combine and bring the mixture together with your hands. Chill for at least 2 hours, or overnight, to firm up the mixture as it is quite soft at this stage.
3. Shape the chilled mixture into 24 little patties about 3-4cm wide, before coating them in the flour. Beat the remaining egg in a small bowl, and place the breadcrumbs in another. Dip the floured patties in the beaten egg, followed by the breadcrumbs to coat. Cover and chill until ready to cook, or you can fry them straightaway.
   Tip

   For speed,you can blitz the watercress with 150g ready-made mayonnaise instead of making your own.
4. Place a large frying pan on the heat, and add 2 tablespoons olive oil. Fry half the prawn cakes for 5 minutes each side until golden and piping hot in the centre; keep warm. Repeat with the remaining oil and prawn cakes.

5. Pile onto a platter and serve with the watercress mayo, lemon wedges and the rest of the watercress leaves to garnish. This recipe contains raw egg.