Heat 1 cup of cream in a saucepan until it just simmers. Remove from heat and stir in chocolate, sugar, espresso, cinnamon, cayenne, and salt until smooth.

Stir in vanilla. Let the ganache cool to room temperature, about 15 minutes.

Whip the remaining 1/2 cup cream to soft peaks. Fold a scoop of whipped cream into the ganache to loosen it, then fold in the rest gently until mixed.

Spoon into cups and chill at least 1 hour. Serve cold.