Add the hot cream to the cold yolks, in a thin stream. The other way round scrambles them on contact.
Take it out while it still wobbles in the middle. A custard sets around 80 C and there is no rescuing one that goes past it. Deeper ramekins want longer, so judge the wobble rather than the clock: 8 oz ramekins can need 50 to 55 minutes.
Skim the foam before it goes in the oven, or it bakes into a pitted skin that will not take a smooth caramel.
An hour in the fridge is the minimum, not the target. Overnight sets better.
Torch within ten minutes of serving. The caramel starts softening against the cold custard straight away. No torch: grill on the top shelf with the ramekins packed in ice, 1 to 3 minutes, then chill again for 20 minutes.
Keeps covered in the fridge up to 3 days. Do not freeze.