Remove the shells from the hard boiled eggs and slice each egg in half.Remove the yolks from the egg halves and place in a bowl. Set the yolks aside.Get enough glasses or mugs for the number of colors you want to use. Fill the mugs or glasses â…” of the way full with cold water.Add 3 drops of desired food coloring along with 1 tsp vinegar to each mug or cup.Place egg whites in the mugs and allow to sit in the food coloring until desired color is reached. I could fit 3 egg whites in each of my mugs at a time.Remove whites from dye and drain on a plate lined with a couple of paper towels.Take the reserved yolks and mash them with a fork. Then mix in the ½ cup mayonnaise with the mashed yolk.Pipe or spoon the yolk mix into the colored egg whites. Makes 20 deviled egg halves.