For the marinade, peel and halve the onion, cut diagonally into strips and sauté in the butter until translucent. Sprinkle with sugar, extinguish with vinegar and soup. Add the spices, let simmer for 10 minutes at low temperature, then set aside to cool. Divide salmon fillet into two portions, place in a mold and pour the marinade. Leave to marinate for at least 1 hour. Peel the carrot and celery, cut the leek in half, rinse and cut all together into fine strips (julienne). Heat oil in a frying pan and sauté vegetables. Remove the fish from the marinade and pour the liquid through a sieve. Boil half of the marinade and cook the vegetables in it for a few minutes until al dente. Pour the other half of the marinade into a sauté pan and boil by half. Add the cream to the reduced marinade. Season with salt, pepper and vinegar and make again until the sauce has a creamy consistency.
Place the fish in the sauce and cook at low temperature for 5-6 minutes.
Lift the salmon pieces out of the broth and arrange on plates. Spread the drained vegetable julienne evenly on top and pour the sauce over it. Sprinkle with freshly chopped parsley.
Our tip: Use sweet red wine for a sweet note and rather dry wine for flavorful, spicy dishes.