For the fried mirror carp with red lentils, first prepare the lentil vegetables. Soak the lentils overnight. Empty into a colander and rinse with cold water. Peel the shallots and celery. Finely chop the shallots, finely dice the celery.
Boil lentils in salted water for 5 minutes, empty into a colander and rinse with cold water.
Heat butter in a pot and sauté shallots and celery in it. Deglaze with white wine, pour in soup and season with cumin, salt and pepper. Let it boil down a bit. Add the cream and let it boil down again. Now add the well drained lentils and simmer for another 2-3 minutes. Season to taste with salt, pepper and lemon juice and thicken with ice-cold butter – the sauce must not boil anymore.
Rinse the carp fillets with cold water and pat dry. Cut into strips about 4 cm wide. Acidify the carp fillets with lemon juice and salt them. Roll in flour, tapping off excess flour.
Heat a mixture of butter and oil in a pan and fry the carp fillets on both sides.
Serve the fried mirror carp with the red lentils.