Set oven to 325°F (160°C). Place 4 ramekins in a deep baking dish.
In a saucepan, warm cream, vanilla, and salt over medium heat until steaming (not boiling).
In a bowl, whisk egg yolks with ½ cup sugar until pale and thick.
Slowly pour hot cream into yolks while whisking constantly. Strain mixture to remove foam.
Divide custard into ramekins. Add hot water to the baking dish until ramekins are half submerged.
Bake 35–40 minutes, until edges set but centers jiggle slightly.
Cool, then refrigerate at least 2 hours (or overnight).
Sprinkle 1 tbsp sugar over each custard. Torch until melted and golden brown, or broil briefly.
