Cut the whites of the eggs into rings and mix the egg yolks with the mayonnaise and mustard. On a platter arrange the lettuce leaves to form a cup, then place the egg whites to form "petals" of a daisy. Place the yolk mixture in the middle. You can also use parsley or dill sprigs as the leaves of the daisy. You can double the recipe and make 2 depending on how many people you are serving. After everyone see the daisy, then they can take rings of egg white and place some yolk in the middle of a ring to eat them together-with a fork, of course.