Slice eggs in half lengthwise, and carefully remove yolks. Set egg whites aside.

Mash yolks in a small mixing bowl. Add mayonnaise, mustard, salt, and pepper; mix well. Stuff egg whites with yolk mixture, shaping mixture into a mound using a metal spatula. Using a knife blade, make three indentations in yolk mixture on top of each egg to resemble a turkey foot. Garnish each egg with fresh parsley, if desired.