In a saucepan, heat whipping cream and scraped seeds from the vanilla bean over medium heat until it gently simmers. Remove from heat and let cool slightly. Preheat oven to 150°C (300°F).
In a bowl, whisk egg yolks with granulated sugar until pale and creamy.
Slowly pour warm cream into the egg mixture, whisking continuously. Strain the mixture into ramekins.
Place ramekins in a baking dish and fill the dish with hot water halfway up the sides of the ramekins.
Bake for 40-50 minutes until the custard sets but remains slightly wobbly in the center. Cool to room temperature, then refrigerate for at least 2 hours (or overnight).
Sprinkle brown sugar evenly over each custard surface. Using a kitchen blow torch, carefully caramelize the sugar until golden and crisp. Alternatively, place under a hot broiler until sugar caramelizes.