A recipe card for Tartre Sauce features a floral pattern, with the title "Tartre Sauce" in cursive. The card lists ingredients: 1/4 cup chopped yellow onions, 1/4 cup chopped bill pickles, 1 tablespoon chopped green olives, 1 tablespoon chopped capers, 1 lemon, juiced finely chopped fresh parsley leaves, 2 teaspoons Dijon mustard, 1 cup mayonnaise, and salt. The card also suggests adding chunky ingredients to a blender bowl for a smooth consistency, and mixing well with parsley.