Bring a pot of water to a rolling boil, then carefully add the 6 large eggs. Maintain a gentle boil for 12 minutes to ensure the yolks are fully cooked but still creamy in the center. While the eggs cook, prepare an ice bath by filling a bowl with ice and cold water. Once the timer goes off, immediately transfer the eggs to the ice bath and let them sit for at least 15 minutes—this stops the cooking process and makes peeling much easier. I find that older eggs (about 7-10 days old) peel significantly better than very fresh eggs, so check your carton date if you have time.

While the eggs chill, mince the red onion as finely as possible and set aside. Chop the fresh parsley and mince the fresh chives, keeping them separate. Measure out the mayonnaise, Dijon mustard, lemon juice, and all the dry seasonings (salt, pepper, paprika, and celery seed) into separate small bowls or ramekins. Having everything measured and prepped before combining makes it easier to taste and adjust the seasoning as you go.

Gently tap each egg on a hard surface to crack the shell all over, then roll it lightly to loosen the shell further. Start peeling from the wider end where the air pocket sits—this makes removal much easier. Rinse each egg under cool running water as you peel to help separate the shell from the egg white. Once peeled, chop the eggs into roughly 1/2-inch chunks and transfer to a medium mixing bowl.

Add the minced red onion, mayonnaise, Dijon mustard, and lemon juice to the bowl with the chopped eggs. Gently fold everything together using a rubber spatula, being careful not to break up the egg pieces too much—you want some texture in the final salad. Sprinkle in the salt, pepper, paprika, and celery seed, then fold again to distribute evenly. Taste the salad and adjust the seasoning if needed; I like to add a touch more lemon juice if it seems a bit heavy or an extra pinch of salt to brighten the flavors.

Fold in the chopped parsley and minced chives just before serving to keep them bright and fresh. Serve the egg salad immediately on bread, crackers, lettuce cups, or in a wrap, or chill until ready to serve. The salad will keep refrigerated in an airtight container for up to 3 days, though the herbs will gradually lose some of their vibrant color.