3 medium eggs
2 x 200-g (7-oz) cans tuna in oil, drained
4 tbsp good-quality mayonnaise
1 tbsp Dijon mustard
salt and black pepper
6 cornichons, finely chopped
½ red onion, finely chopped
2 cooked beetroots (beets), finely chopped
1 large crusty ciabatta loaf
100g (3½oz) watercress, or other salad leaves
Cook the eggs in a pan of boiling water for 8 minutes. Drain and run under cold water until completely cool, then peel and set aside.
Flake the tuna into a bowl and add 3 tablespoons of the mayo, the mustard, a little salt and plenty of black pepper. Stir in the cornichons and red onion, then gently fold through the beetroot – you want a light mottled pink mixture.
Split the ciabatta loaf in half lengthways and spread with the remaining mayo on both sides.
Thinly slice the hard-boiled eggs and lay on the bottom layer. Top with a generous layer of tuna, followed by handfuls of green leaves. Cut into thick slices and serve.