Prepare hard boiled eggs ahead of time. You can keep hard boiled eggs in the refrigerator for a couple of weeks.
6 hard boiled eggs 3 tablespoons sour cream 1/2 teaspoon mustard 1 teaspoon vinegar
Peel eggs. Slice a thin piece from each pointy end, for a stable end to sit on. Slice each in half crosswise, not lengthwise. Remove yolks and put them in a bowl. Mash the yolks, then add remaining ingredients. Stir with a spoon, mixing until smooth. Spoon the yolk mixture into the egg halves. Serve.