Halve or quarter eggs; scoop yolks into a small bowl. Mash well; add mayonnaise and Dijon until desired consistency is reached.
Stir in white part of sliced onion and most of the chopped parsley. Taste and add salt and pepper to taste.
Using a small teaspoon or pastry bag, fill egg white halves or quarters.
Sprinkle with sliced green onion and remaining parsley. Sprinkle with a
little pepper and/or paprika, if desired.