Yield:    Approximately 1¼ cups Ingredients: 1 large egg 3 teaspoons freshly squeezed lemon juice, or to taste 1 teaspoon yellow mustard powder (NOTE: You can use 1 tablespoon mustard powder without creating a strong mustard flavor and with the added emulsification qualities of the mustard, the mixture will thicken more quickly.) ½ teaspoon finely ground…