Boil eggs in water for 9–10 minutes until hard-boiled.
Transfer eggs to cold water, peel, and chop into small pieces.
Finely chop dill pickles and onion.
In a mixing bowl, combine chopped eggs, pickles, and onion.
Add mayonnaise, mustard, salt, and black pepper.
Mix gently until creamy and well combined.
Chill for 15–20 minutes for best flavor, then serve in sandwiches, wraps, or with crackers.