01 - Place eggs in a medium saucepan and cover with cold water by 1 inch. Bring to a rolling boil over medium-high heat, then reduce to a gentle simmer and cook for 9-10 minutes.
02 - Transfer eggs immediately to an ice bath or run under cold water until completely cooled. Peel off the shells and roughly chop the eggs.
03 - In a mixing bowl, combine mayonnaise, Dijon mustard, lemon juice, celery, red onion, and chives. Fold in the chopped eggs and stir gently until evenly coated. Season with salt and pepper to taste.
04 - Carefully separate lettuce leaves from the head, rinse under cold water if needed, and pat thoroughly dry with a clean towel.
05 - Spoon the egg salad evenly onto the center of each lettuce leaf. Add optional toppings such as sliced radishes, extra herbs, or a sprinkle of paprika if desired.
06 - Fold the lettuce leaves around the filling and serve immediately while the lettuce is crisp.