Preheat oven to 325°F.
Combine the cream and the lavender leaves in a small heavy saucepan over medium heat and bring to a simmer. Remove the pan from the heat and let the mixture stand for 10 minutes.
Whisk egg yolks, 1/2 cup sugar and the vanilla in a medium sized bowl until well blended. Slowly add the cream mixture and whisk constantly until it is blended. Strain the mixture through a fine sieve then divide the mixture between 4 6-oz ramekins. Place the ramekins in a baking pan and add enough hot water come half way up the sides of the ramekins. Cover the pan with aluminum foil and bake until the custards are just set, approximately 40 minutes. Do not overbook or the custard will be "tough".
Two hours before serving:
Preheat broiler. Sprinkle 2 teaspoon sugar atop each custard. Place dishes on small baking sheet. Broil until sugar just starts to caramelize, rotating sheet for even browning, about 2 minutes. Chill until caramelized sugar hardens, about 2 hours.