Method
For the potatoes, heat a splash of oil in a large, deep frying pan over high heat. Add the onion, garlic and chilli and cook until softened.
Step 2Add the potato and chicken stock and bring to the boil. Reduce to a rolling simmer and cook for about 20 minutes or so. What we’re looking for is for the stock to reduce as the potato cooks, resulting in a thick sauce when they’re done.
Step 3Once the potato is tender, season with salt and pepper and stir through the lemon zest and juice, dill and spring onion. Meanwhile, mix the rock salt through the egg whites in a large bowl to form a thick paste.
Step 4Give the trout a good hit of pepper and place a sprig of dill and two slices of lemon in the belly cavity of each fish. Transfer the fish to a large roasting tin and cover the body of the trout completely in the salt mix.
Step 5Bake for 20–30 minutes – a 300 g trout will take about 20 minutes – just add an extra 5 minutes per 100 g.
Step 6To serve, crack the salt crust and pull it away from the top of the fish. Peel back the skin (this will be pretty salty) and spoon some crème fraîche over the flesh or serve it alongside the trout. Serve up with the chicken-stock potatoes and you have yourself a meal.