Poached salmon with mousseline sauce is a classic French dish that combines tender poached salmon with a rich and creamy sauce. The salmon is gently cooked in a flavorful broth until it is perfectly tender and flaky. The mousseline sauce, made with butter, egg yolks, and lemon juice, adds a luxurious touch to the dish. This elegant and delicious recipe is perfect for a special occasion or a fancy dinner party.