Lie your mint leaves onto a nonstick baking sheet. Beat an egg white in a small bowl until it turns frothy and then use a pastry brush to apply a thin layer on both sides of the leaf. Allow it to dry for about 30 seconds, and then sprinkle each side with crystallized sugar. Wait 24 hours for the leaves to dry completely and don’t cover them while they are drying! You can store them in an airtight container for future garnishing!