200g (7oz) new potatoes
small bunch of watercress, stalks removed
1 filleted smoked trout, about 200g (7oz), skinned
2 large eggs
salt and freshly ground pepper
40g (3½ tbsp) softened butter
5 tbsp olive oil
juice of 3 lemons
2 spring onions (scallions), finely sliced
2 tbsp double (heavy) cream
1 tbsp grated fresh horseradish
Boil the new potatoes in their skins for about 20 minutes until tender, then drain.
Finely shred the watercress leaves, flake the smoked trout and mix them together.
Break the eggs into a bowl, beat them very lightly and season with salt. Gently heat a 20 cm (8in) non-stick frying pan with a very flat base, then brush with a little softened butter. Pour one-quarter of the beaten egg into the pan and tilt to spread the egg thinly and evenly over the surface, as if you were making a crêpe. Cook over a low heat for about 1 minute, until the omelette has set. Remove from the pan and slide on to a sheet of greaseproof paper or a plate. It should be cooked on one side only to keep it soft and malleable. Make three more omelettes in the same way.
Peel the cooked potatoes and grate coarsely. Add the olive oil and the juice of 2 lemons, and season with salt and pepper. Add the spring onions and mix delicately.
Spread the trout and watercress mixture delicately over the omelettes. Mix the cream, remaining lemon juice and the horseradish together, season to taste and drizzle over the trout. Roll up the omelettes gently but firmly and evenly. Divide the potato between 2 plates and arrange 2 omelettes on each plate. Cut the omelettes in half on the diagonal to reveal the filling. Serve as a starter or light lunch.