Preparation

Make the biscuit dough

• In the bowl of a food processor, pulse the flour, sugar, baking powder, and salt to combine, 15 to 30 seconds.
• Add the butter and pulse until the mixture resembles coarse meal with pieces no larger than the size of a pea, 1 to 2 minutes more.
• Transfer to a medium bowl. Stir in the pistachios.
• 在中心的碗,倒入cream, and toss well to combine. Gently combine the mixture into a dough, being careful not to overmix (the mixture will be slightly tacky).
• Cover the bowl with plastic wrap and refrigerate while you make the filling. (The biscuit topping can be made up to 1 day ahead; keep covered in the refrigerator.)

Make the filling

• In a small bowl, combine the sugar and cornstarch (if your berries are especially juicy, add an additional 1 or 2 tsp. of cornstarch). In a large bowl, toss the blackberries with the sugar mixture.

Assemble and bake the cobbler

• Position a rack in the center of the oven and heat to 400°F.
• Butter a shallow 3-quart baking dish (or individual dishes; see tip). Pour the fruit into the prepared dish. Using two spoons or a scoop, dollop the dough over the fruit about 1 inch apart.
• Transfer the cobbler to the oven, and bake until the biscuits are evenly golden and the fruit filling is bubbly in the center of the dish, 30 to 35 minutes. Rotate the cobbler halfway through baking time for even browning. If browning too quickly, reduce the oven temperature to 375°F and tent the baking dish with foil. Let the cobbler cool for at least 45 minutes before serving warm.