Mascarpone Cream Tart with Blackberries

For Pastry Dough:

Combine the flour, sugar, and salt in a small bowl and place in the freezer for 30 minutes. Put the flour mixture in the bowl of a food processor fitted with a steel blade. Add the butter and shortening and pulse about 10 times, or until the butter mixture is in the size of peas. Add the ice water and process until the dough comes together. Transfer to a well-floured work surface and form into a disk. Wrap the disk in plastic and chill for at least 30 minutes.

Meanwhile, preheat the oven to 375ºF.

Roll out the dough and fit into a 10-inch fluted tart pan with a removable bottom. Cut off any excess dough from around the edges. Prick the bottom of the shell all over with the tines of a fork. Line the tart shell with a piece of buttered aluminum foil, butter side down, and fill with dried beans. Bake for 10 minutes. Cool slightly.

For Mascarpone Filling:

In a large bowl, combine mascarpone, sugar, eggs, vanilla and cornstarch, stirring until smooth and creamy. Spoon mascarpone mixture into the baked tart shell and bake for about 25 minutes.

To Assemble: