Preheat your oven to 325°F (160°C).
In a saucepan, heat the heavy cream and vanilla bean until just simmering. Remove from heat and let it cool slightly.
In a bowl, whisk together the egg yolks and ½ cup sugar until pale and thick.
Slowly pour the warm cream into the egg mixture, whisking constantly.
Strain the mixture through a fine sieve into a large measuring cup or bowl.
Divide the custard mixture among the ramekins.
Place the ramekins in a baking dish and add hot water to the dish until it reaches halfway up the sides of the ramekins.
Bake for 40-45 minutes, or until the custards are set but still slightly jiggly in the center.
Remove the ramekins from the water bath and let them cool to room temperature. Then refrigerate for at least 2 hours.
Before serving, sprinkle the tops with the remaining sugar and caramelize with a blowtorch until golden and crisp.