Preheat oven to 325°F (160°C). Place ramekins in a large baking dish.
In a saucepan, heat heavy cream and vanilla bean (or extract) over medium heat until it just begins to simmer. Remove from heat and let it steep for 10 minutes.
In a mixing bowl, whisk egg yolks, sugar, and salt until pale and slightly thickened.
Slowly pour the warm cream into the egg mixture, whisking constantly to prevent scrambling.
Strain the mixture through a fine-mesh sieve to ensure a smooth custard.
Divide custard evenly among the ramekins. Fill the baking dish with hot water halfway up the sides of the ramekins to create a water bath.
Bake for 40-45 minutes until the custards are set but still slightly jiggly in the center.
Remove from the water bath and let cool at room temperature for 30 minutes, then refrigerate for at least 2 hours (or overnight).
Before serving, sprinkle 1 tsp of granulated sugar evenly over each custard.
Caramelize the sugar using a kitchen torch, moving in a circular motion until golden and crisp. Alternatively, place under a broiler for 1-3 minutes, watching closely.
Let the caramelized topping cool for 1-2 minutes before serving to allow it to harden.
Notes
For added flavor, infuse the cream with citrus zest or coffee. Store leftovers in the fridge for up to 2 days (without caramelized topping).