Using a sharp paring knife, cut sliver of egg from bottom of each boiled egg so that eggs will sit level horizontally. Cut 2 wedges from each side of top half of eggs so that eggs will resemble baskets with a handle. Reserve cut pieces of eggs. Using a small spoon, gently scoop out egg yolks and add to reserved egg whites. Place egg white baskets in a covered container and refrigerate until needed.
Using a pastry blender or 2 forks, finely chop reserved egg pieces and yolks.
In medium bowl, stir together chopped egg, mayonnaise, celery, relish, mustard, salt, and pepper until combined. Cover and refrigerate until cold, 1 to 2 hours.
Fill each egg white basket with egg salad.
Garnish with a sprinkle of paprika and with watercress, if desired. Serve cold
Recipe by TeaTime Magazine at https://teatimemagazine.com/egg-salad-baskets/