Salt and pepper the filleted fish, strew with the juice of 1/2 lemon. Dip the fillet in the whisked with 1 tablespoon of water egg. Cut potato into circles and put it onto the fillet like scales, then turn the fillet out, and put potato slices on this side as well. Fry the fish backed with potato at both sides, and then heat it through in the oven.

For the sauce, thinly cut pepper and spring onions, sauté in oil, add 1/2 cup of water or bouillon, and stew until soft, then force through the sieve. Add shredded garlic, salt, pepper, 1 teaspoon of lemon juice and bring to a boil. Chill and combine with yoghurt.

When serving, side with the sauce, place the fish, garnish with lemon zest and greens.