Hard-boil the eggs
Cool the eggs in ice water
Peel the eggs
Slice the eggs in half lengthwise
Remove the yolks
Place the yolks in a bowl
Mash the yolks until smooth
Add mayonnaise
Add mustard
Add salt
Add black pepper
Add vinegar or pickle juice
Mix until creamy
Taste and adjust seasoning
Spoon or pipe the filling into the egg whites