1. Preheat the oven to 325°F (160°C). Place 12 ramekins in a large roasting pan.
2. In a saucepan, combine the heavy cream, milk, vanilla bean, and its seeds. Heat the mixture over medium heat until it just begins to simmer. Remove from heat and let it sit for 15 minutes to infuse the flavors.
3. In a mixing bowl, whisk together the egg yolks, sugar, and salt until well combined and slightly thickened.
4. Slowly pour the warm cream mixture into the egg yolk mixture, whisking constantly to avoid curdling the eggs.
5. Strain the custard through a fine-mesh sieve into a pouring jug to remove the vanilla bean and any egg solids.
6. Divide the custard among the ramekins, filling them almost to the top.
7. Carefully pour hot water into the roasting pan, around the ramekins, to create a water bath that reaches halfway up the sides of the ramekins.
8. Bake the crème brûlées in the preheated oven for 40-45 minutes, or until the edges are set but the centers are slightly jiggly. Remove from the oven and let them cool in the water bath for 30 minutes.
9. Remove the ramekins from the water bath, cover with plastic wrap, and refrigerate for at least 4 hours or overnight to chill and set.
10. Just before serving, sprinkle a thin, even layer of granulated sugar on top of each crème brûlée. Caramelize the sugar using a kitchen torch or by placing them under the broiler for a few minutes until the sugar caramelizes and forms a crispy crust.