In a large bowl, mix together the sugar, cornstarch, tapioca, and salt. Add the berries and toss with your hands until the berries are evenly coated.

Roll out the pie dough according to the directions in the Butter Pie Crust recipe. Pile the berries into the dough-lined pie pan, sprinkling any remaining dry ingredients on top. Dot the surface with the butter, cover the berry mixture with the top crust and seal the edges by fluting.

Cut 5 or 6 slits in the top crust to let steam escape during cooking. Heat the oven to 400 degrees F while you chill the pie in the refrigerator for 15 to 20 minutes.

Put the pie on a baking sheet to catch any drips, bake it in the hot oven for 15 minutes, and then reduce the temperature to 350 degrees F. Continue baking until the crust is golden and the filling juices that are bubbling through the vents and edges are thick, glossy, and slow, another 50 to 60 minutes. For the best texture for serving, cool the pie completely (which may take up to 5 hours), and then reheat slices or the whole pie just slightly before serving. (Cooling completely allows the filling juices to firm up, while a quick reheat makes the pastry nice and flaky.) You can serve the pie while it's still warm, but the filling will be slightly liquid; definitely don't serve the pie hot, as the juices will be too fluid.

1. Cut the butter into 1/2-inch cubes. Dump the flour, sugar, and salt into the bowl of a stand mixer fitted with the paddle attachment (or in a large bowl, if mixing the dough by hand). Mix for a second or two to blend the dry ingredients. Add the butter and then, running the mixer on low (or by hand with two knives or a pastry cutter), work the mixture until it's crumbly and the largest pieces of butter are no bigger than a pea (about 1/4 inch).

2. The butter should remain cold and firm. To test it, pick up some butter and pinch it between the thumbs and forefingers of both hands to form a little cube. If the butter holds together as a cube and your fingers are not greasy, then the butter is still cold enough. If your fingers look greasy, put the bowl in the refrigerator for 15 minutes to firm up the butter before adding the water.

3. As the mixer turns on low (or tossing with a fork if mixing by hand), sprinkle the cold water evenly over the flour and butter. Work the dough until it just pulls together as a shaggy mass.

4. To roll out the dough for a double-crust pie: Cut the dough in half and pat each piece into a thick flattened ball. Lightly flour your work surface and tap one of the dough balls down with four or five taps of the rolling pan. Begin rolling from the center of your dough outward. Stop the pressure 1/4 inch from the edge of the dough. Lift the dough and turn by a quarter and repeat the rolling until the dough is at least 12 inches in diameter. Be sure to re-flour the work surface if your dough is sticking.

5. Using a pot lid or a circle of cardboard as a template, trim the dough to form a 12-inch round (this should give you a 1-1/2-inch margin all around your 9-inch pie pan). Fold the dough in half, slide the outspread fingers of both hands under the dough, and gently lift it and transfer it to the pie pan. Unfold and ease the dough round into the bottom of the pie pan without stretching it.

6. Roll out the other dough ball and cut a second 12-inch round to be used as the top crust.