Preheat oven to 325°F (160°C)
Place 6 ramekins in a deep baking dish
In a saucepan, heat 2 cups (480 ml) heavy cream with 1 vanilla bean (split) or 2 tsp vanilla extract until steaming (do not boil)
In a bowl, whisk 5–6 egg yolks with 1/3–1/2 cup (65–100 g) sugar until smooth and slightly thickened
Slowly whisk the hot cream into the yolk mixture to temper
Strain through a fine-mesh sieve into a pouring pitcher or bowl
Divide custard among ramekins
Pour hot water into the baking dish until it reaches about halfway up the sides of the ramekins
Bake 30–40 minutes, until edges are set and centers jiggle slightly
Remove ramekins from water bath and cool to room temperature
Refrigerate at least 4 hours, preferably overnight
Just before serving, sprinkle a thin, even layer of sugar (about 1–2 tsp per ramekin) over each custard
Caramelize sugar with a kitchen torch until browned and hardened
Rest 1–2 minutes, then serve immediately