In a heavy saucepan, combine cream, macadamias, coffee, and vanilla bean. Bring to a boil, then turn off heat and allow to steep for one hour. Preheat oven to 325 degrees.
In a large bowl, beat 1/3 cup sugar and egg yolks together until pale and thick. Strain cream mixture through a very fine sieve into the egg yolk mixture. Discard strained macadamias, ground coffee, and vanilla bean. Stir until smooth. Pour mixture into six ramekins in a shallow baking pan and add enough hot water to come half way up the sides of the ramekins. Bake for about 30 to 40 minutes, or until custard is set around the edges but still a little loose in the center. Remove from baking pan, let cool, then refrigerate until cold.
Preheat broiler.
When ready to serve, sprinkle 2 Tablespoons sugar on top of each of the custards. Place under the broiler until the sugar caramelizes, taking care not to let them burn. Serve immediately