Bring a pot of water to a boil, then reduce the heat to low to stop the bubbling. Using a skimmer, gently lower the room-temperature eggs into the water.
Increase the heat to high and boil the eggs for 12 minutes.
Transfer the boiled eggs to an ice water bath for at least 15 minutes to halt the cooking process and cool completely.
Peel the eggs and slice or chop them to your desired texture.
In a mixing bowl, combine the chopped eggs with the red onion, chives, parsley, mayonnaise, Dijon mustard, lemon juice, kosher salt, and black pepper. Stir until thoroughly combined.
Serve immediately from the bowl, or use as a filling for sandwiches or wraps.