In a medium bowl and using a pastry blender, cut eggs into fine pieces. Add mayonnaise, mustard, tarragon, salt, and pepper, stirring until combined. Place in a covered container, and refrigerate until cold, approximately 4 hours. (Egg salad can be made a day in advance and refrigerated until needed.)
Spread approximately 3 tablespoons egg salad mixture onto each of 3 slices bread. Top each with another bread slice, and spread another 3 tablespoons egg salad on top. Top with a third bread slice to make a triple-stack sandwich.
Using a serrated bread knife, trim crusts from all sides of sandwiches, and discard. Cut each sandwich into 2 finger sandwiches.
Garnish with tarragon sprigs, if desired.
Course: Afternoon tea
Cuisine: British
Keyword: afternoon tea, Egg salad, Tarragon, tea time