Clean the lettuce and cut into strips. Sweat the onions in butter until translucent. Add the oatmeal and let it sweat with it. Add the salad. After stirring continuously for 1-2 minutes, pour in the vegetable stock and bring everything to a boil. Season well with lemon juice, turnip tops, pepper, cayenne pepper and nutmeg.
Puree the soup, heat again, stir in the cream and season again to taste. Mix the salmon with the dill. Serve the soup and sprinkle with salmon and dill.