The main thing is to add enough mayo to make it really moist.
2 hard boiled eggs cut in half
3-4 tbsp mayo or miracle whip (enough to make it good and creamy)
small squirt of yellow mustard (about 1/8 tsp at most)
pinch of salt
generous amount of pepper
Cut eggs in half and remove yolk. Combine yolk and all other ingredients in a bowl and smash with a fork or beat with egg beaters until creamy. Pipe or spoon mixture back into each egg. (Only in the part where the yolk was.)
Sprinkle each egg with a pinch of paprika and garnish with finely chopped parsley and/or green onion curls. (see how to, below)
How to make green onion curls
Trim the green parts of the green onion into long narrow strings. Place in a bowl of ice water. (make sure they are submerged) after about a minute, they will curl themselves.