Chocolate Truffle Tart

INGREDIENTS

For the tart shell:

large egg yolk

1 tbsp

heavy cream

1/2

tsp. vanilla extract

1 cup

all-purpose flour, plus more for dusting the work surface

1/4 cup

Dutch-process cocoa powder

2/3 cup

confectioners’ sugar

1/4

tsp. salt

8 tbsp

cold unsalted butter, cut into ½-inch cubes

For the filling:

12 oz

good quality bittersweet chocolate, finely chopped

6 tbsp

unsalted butter, softened

1 cup

heavy cream

1 tbsp

liqueur, such as Kahlua, brandy, or dark rum (optional)