Mix the yoghurt, mustard and salt in a bowl. Peel the potatoes, cut into approx. 2mm thick slices, mix. Spread the potatoes on an oven tray lined with baking paper.
for approx. 15 mins. in the bottom half of an oven preheated to 220°C.
Pare down the thick midribs of the leaves. Season the salmon fillets, wrap each in two lettuce leaves, place on top of the potatoes and finish cooking for approx. 15 mins.