Purple Sweet Potato Pie

Mix pastry flour, all-purpose flour and 1/2 teaspoon salt in a large bowl or pulse in a food processor. Cut in cold butter using a pastry blender or two knives or by pulsing in the food processor until the butter forms pebble-size pieces. Add water, 1 tablespoon at a time, until the dough is evenly moist (but not wet) and is just starting to clump together, being careful not to overmix. Pat the dough into a 5-inch disk. Wrap in plastic and refrigerate for at least 1 hour and up to 1 day.

Prick sweet potatoes all over with a fork. Microwave on High until tender all the way to the center, 10 to 15 minutes. (Alternatively, place in a baking dish and bake at 425 degrees F until tender all the way to the center, about 1 hour.)

Meanwhile, preheat oven to 350 degrees F.

Remove the dough from the refrigerator and let stand for 5 to 10 minutes to warm slightly.

When the sweet potatoes are cool enough to handle, scoop the flesh into the food processor (discard skins). Pulse until smooth. Add evaporated milk, brown sugar, eggs, butter, brandy, vanilla, nutmeg, allspice and salt. Puree until very smooth, scraping down the sides as needed.

Roll the dough out on a lightly floured surface into a 12-inch circle. Transfer to a 9-inch deep-dish pie pan. Tuck the overhang under and crimp the edge with a fork or flute it between your thumb and index finger. Pour the filling into the crust.

Bake the pie until puffed and just firm in the center, 50 to 55 minutes. Let cool on a wire rack for at least 30 minutes before serving.