To Make the Crust:

1. In a food processor, pulse flour, icing sugar, and salt.

2. Add cold butter and pulse until the mixture is crumbly.

3. Add egg yolk and pulse until dough forms clumps.

4. Press dough into a disc, roll between parchment to ⅛-inch thickness.

5. Chill for 2 hours (or freeze for 1 hour), then press into a 9-inch tart pan. Prick the base with a fork.

6. Freeze for 30 minutes. Bake at 400°F (200°C) for 25 minutes with foil and pie weights. Remove weights and bake 7–10 minutes more. Cool completely.

To Make the Filling:

1. In a saucepan, heat cream with cinnamon, nutmeg, and cayenne until boiling. Remove from heat.

2. In a skillet, melt sugar over medium heat until it turns amber. Carefully stir in the hot cream mixture (it will bubble).

3. Steep 1 hour, then strain to remove cinnamon sticks.

4. Reheat cream, pour over chopped chocolate. Let sit 1 minute, then stir until smooth.

To Assemble:

1. Pour ganache into the cooled crust.

2. Chill at least 2 hours or until set.

3. Serve topped with whipped cream or berries if desired.