First, I only really make this pie if I've picked blackberries somewhere. The reason? It's too expensive to buy this many blackberries from the store, and they don't taste nearly as good as when you pick them fresh. Or if in season, buy a flat at a great discount at the farmer's market.
Step one: rinse about 10 cups of blackberries very gently to test the dust off. Put in about 1 cup of sugar and juice from a big meyer lemon (about a 3/4 cup) or 1.5 eureka or lisbon lemons (about a 1/2 cup).
Step two: make a pate brisee crust.
1.5 cubes or 12 T butter
2.5 c sifted flour
1 T evaporated cane juice organic sugar
1 t salt
Sift the flour, sugar and salt into a metal bowl. Cut the butter into the flour, sugar, salt mixture a pastry cutter, working until the butter is in very small pieces, about 1/4" cubes or smaller and coated with the dry mixture. Be sure not to touch the mixture with your hands which will warm the butter and melt it. Just use a knife to scrape it from the pastry cutter, and work quickly to keep the mixture cold. Add 1/4 cup cold water and using a fork, blend the mixture into a dough. Carefully add a tablespoon at a time of additional cold water until the dough is crumbly but there is only a small amount of loose flour outside the main dough ball. Working quickly, take the dough and place it in the center of a large piece of plastic wrap. Then fold the wrap over teh top of the dough, press everything together and quickly and lightly form into a disc. Place the neatly wrapped disc into a ziplog bag. Put into the fridge for at least a half hour.
Step three: roll out the crust.
Place about a half cup of flour over a work surface at least 24" x 24" and then take half the dough from the plastic. Leave the other half back in the fridge. Put flour on a rolling pin, dust the top of the half disc, and carefully roll out the crust. Once it's about 1/8" thick uniformly by about 15" in diameter, lift the dough in a single piece into a 10" pie pan. Place the fruit into the pan with crust. Cut the edge of the crust leaving about a half inch around the outside edge of the pan. Set the fruit / crust in pan into the fridge.
Get out the other half of the dough rolling it out using the instruction above. Once the dough is approximately 15" in diameter, cut out a shape or two (star, moon, circle, etc). Pull the fruit / pan out of the fridge. Carefully lift the dough over the pan, and press the edges together either with fork tines, or with a three finger press to make ridges.
Mix well in a small bowl:
1 T water
Brush the egg mixture over the top of the pie crust.
Step four: bake it.
Bake the pie in a 350 deg F oven for 50 minutes (10 min more if at high altitude). Crust will be lightly browned and the berries will be bubbling inside the holes. Let cool and serve with creme fraiche, vanilla ice cream, whipped creme, or plain.
And here is the finished product: