Lina Wachtelborn Meier, The Art of German Cooking and Baking… (1922)
“ The water is drained off and the vegetables mixed with the potatoes, truffles, salmon, sardines and olives, which have also been cut into pieces. The mayonnaise dressing is made by stirring the 4 yolks of eggs into cream; add lemon juice, mustard, pepper and salt and cook in double boiler until thick, stirring constantly. After it has cooled off, stir in the oil. The salad is mixed carefully with one half of this dressing. The head lettuce leaves are picked off and placed into the salad dish, the salad piled up in the center of it and the rest of the dressing poured over. ”
