white wine or rice vinegar
kosher salt and black pepper
- Peel the hard-boiled eggs. Cut in half lengthwise. Press the yolks through a strainer into a small bowl.
- Add the mustard, mayonnaise, vinegar, and a pinch each of salt and pepper and combine.
- Place yolk mixture in a resealable plastic bag, trim ½ inch from a corner of the bag, and pipe the filling into the reserved whites.