Place eggs in a pot and cover with cool water.
Bring to a boil over medium heat.
Cover the pot and remove from heat.
Let eggs sit in the hot water for 10 to 12 minutes.
Transfer eggs to an ice bath.
Cool completely.
Peel eggs.
Slice eggs lengthwise.
Remove yolks and place yolks in a bowl.
Mash yolks with mayonnaise, Dijon, vinegar, garlic powder, onion powder, salt, and pepper.
Mix until smooth.
Add green food coloring if desired for tree designs.
Spoon or pipe yolk filling into egg whites.
Add garnish if desired.
Chill until serving.