2 1/2 cups all-purpose flour, plus more for dusting
1/2 cup sugar
Kosher salt
Zest of 1 lemon
1 vanilla bean
2 sticks (1/2 pound) unsalted butter, cut into 1/2-inch pieces and chilled, plus more for greasing the tart pan
3 large organic egg yolks
1/4 cup grappa (or rum or water)
8 ounces mascarpone
1/2 cup heavy cream
3 tablespoons grappa (or rum or water)
3 tablespoons sugar
1 vanilla bean, seeded
1 pint raspberries
1 pint blackberries
Shaved dark chocolate, for garnish