If you wanted to keep this vegetarian you could swap the salmon for some crumbled blue cheese. Slices of prosciutto draped over the tart would also work very well. If you wanted to be a bit fancier you could make individual tarts.
- 300g waxy new potatoes such as Charlotte, halved if large
- 1 tablespoon sunflower or rapeseed oil
- 4 leeks, trimmed, washed and cut into 1cm thick rounds
- 175g mascarpone
- 1 tablespoon finely chopped dill
- 1 tablespoon finely chopped flat-leaf parsley
- 320g sheet puff pastry (preferably all-butter)
- 300g sliced smoked salmon
- Cook the potatoes in salted boiling water for 15-20 minutes until cooked through. Drain and leave to cool. Peel off the skins and cut into 1cm thick rounds.
- Heat the oil in a saucepan and add the leeks. Cook over a moderate heat for 10 minutes, stirring to prevent the leeks from browning. Take off the heat and leave to cool slightly. Stir in the mascarpone followed by the sliced potatoes and herbs. Taste and season with salt and ground black pepper.
- Heat the oven to 200˚c, fan oven 180˚c, mark 6. Unroll the sheet of pastry and lay on a baking sheet. With the tip of a knife score a margin of about 1cm around the edges of the pastry. Spread the leek and potato mixture evenly over the pastry, keeping within the margin. Cook in the oven for 25-30 minutes. Take out of the oven and leave for 5 minutes before draping over the smoked salmon.