Split the vanilla bean lengthwise and scrape out the seeds, then mix them with the powdered sugar.

In a saucepan, heat the milk, heavy cream, vanilla sugar, split vanilla bean, and vanilla extract over low heat for 5 minutes, stirring with a whisk to prevent the milk from sticking.

Remove from heat, cover, and let steep for 20 minutes. Then remove the vanilla bean.

Add the egg yolks and whisk until the mixture is smooth and well combined.

Divide the mixture among 6 ramekins, then bake for 40 to 45 minutes at 300°F (150°C).

Let cool, then refrigerate (ideally overnight or at least during the day if serving in the evening).

When ready to serve, sprinkle brown sugar on top and caramelize with a kitchen torch. Serve immediately.