Bring a small pan of water to the boil and simmer the potatoes for 12-15 mins until tender. Drain and leave to steam-dry. Return the potatoes to the pan and mash with the butter. Stir in the flour, baking powder, 1/2 tsp salt and a good grinding of black pepper.

Tip the potato mixture onto a lightly floured work surface and press into a circle roughly 15cm wide and about 1cm thick, then cut into four wedges.

Heat a splash of oil and a knob of butter in a non-stick skillet or frying pan over a medium heat, and fry one of the scones for 3-4 mins on each side until golden brown. Repeat with the remaining scones.

Divide the scones and smoked salmon or trout between two plates, then top with the soured cream and chopped chives. Season and serve.