Defrost fish and peas at room temperature. Peel, wash and halve potatoes and cook in boiling salted water for about 20 minutes. Peel onion and cut into fine cubes. Wash lemon hot, grate dry and peel in thin strips with a zest ripper. Halve the fruit and squeeze juice out of one half. Cut the remaining half into slices.
Wash the fish, dab dry and season with salt, pepper and 1-2 tbsp. lemon juice. Heat 1 tablespoon of fat and sauté the onion cubes for about 6 minutes. Add peas after 2 minutes. Season to taste with salt and sugar. Whisk the egg in a deep plate. Turn the fish one after the other in flour, egg and almonds. Heat 2 tablespoons of fat in a frying pan and fry the fish for about 4 minutes, turning. Add lemon slices for the last minute and fry. Heat milk and 50 g fat in a pan. Drain the potatoes, add the milk mixture and mash with a potato masher until mashed. Season to taste with salt and nutmeg.
Turn the fish one after the other in flour, egg and almonds. Heat 2 tablespoons of fat in a frying pan and fry the fish for about 4 minutes, turning. Add lemon slices for the last minute and fry. Heat milk and 50 g fat in a pan. Drain the potatoes, add the milk mixture and mash with a potato masher until mashed. Season to taste with salt and nutmeg. Serve the mashed potatoes, peas and fish with lemon slices. Sprinkle with lemon zests
Waiting time approx. 1 hour