Preheat oven to 325F/165C (conventional) and have 4-5 ramekins ready.
Place the cream, coffee, vanilla and whiskey in a saucepan and heat gently, without boiling, for 5 minutes.
Whisk the eggs and sugar together, then pour on the warm cream, whisking well.
Strain into individual ramekins (it should make 4-5 portions) and place in a baking dish containing enough water to come two-thirds of the way up the side of the dishes.
Bake for 30-40 minutes or until the cream is just set. Chill until cold.
Cover the top of each ramekin with 1-2 tsp caster sugar and heat with a blowtorch until melted and crisp. If you don't have a blowtorch, the sugar can be melted until a grill/broiler.