For the pie shell (makes enough for 2 single crust pies):
2.5cupsall purpose flour(10.6 ounces), plus more for rolling
1/2cupcold butter, diced
8to 9 tablespoons water
1beaten egg to brush the pie shell
For the filling:
3poundsfrozen mixed berries(strawberries, blueberries, raspberries, and blackberries), defrosted and drained very well
1smalllemon, juiced and zested
1/2cupsugarup to 3/4 cup
For the topping:
1/2cupall purpose flour
For the pie shell:
In a large bowl, combine dry ingredients
Add cold butter and shortening and cut in with pastry cutter or 2 knives until the butter and shortening are pea-sized and evenly distributed.
Add the vinegar and then drizzle the water, trying to distribute it evenly over the surface.
Using the pastry cutter or your hands, works the liquid into the dough until it comes together. Use more water if necessary but try to use only what is needed.
Shape the dough into 2 disks (mine were about 10.25 ounces each), cover with plastic wrap or place in a plastic bag, and freeze for about 15 minutes. You will only need one of these disks (save the other for another pie)
Remove one disk from freezer, flour each side well, and roll out from the center, to a diameter that is 1 inch larger than your pie dish (usually 11 to 13 inches). Use liberal amounts of flour, roll from center, turn, repeat and don't be tempted to throw the dough at the wall if it sticks.
I used a fondant matte with circle guides that was tremendously helpful in rolling out my dough; this also helped prevent the dough from sticking and was useful to invert and peel the dough onto the pie dish.
You can also transfer the dough to the pie plate by either folding the dough around the rolling pin, or carefully folding it in quarters.
Arrange the dough in the pie dish and crimp along the edges
Preheat the oven to 350 degrees and then place the pie shell in the fridge or freezer for 20 minutes to allow the dough to rest (this helps prevent the dough from losing its shape during the baking period)
Remove the pie from the fridge or freezer and blind bake the shell using pie weights or dry beans/rice arranged on top of wax paper or parchment paper.
Brush the edges of the pie shell with beaten egg and bake for about 20 minutes
In the meantime, make the filling
To make the filling:
The fruit must be well drained. If in doubt, let it sit out longer and drain more.
Once the fruit has been thoroughly defrosted and drained, combine all ingredients in a large sauce pan and heat gently over low to medium heat until thickened, about 3 to 4 minutes. Stir often to prevent burning. The mixture will thicken a bit further as it cooks more and more importantly when it cools after baking.
Remove from burner and set aside
To make the crumb topping
Combine all ingredients in a small bowl and mix well with fingers. Do not use food processor or the oatmeal will become too fine and the texture will change.
To make the pie
Preheat oven to 375 degrees.
Add precooked filling to the blind-baked pie shell and sprinkle the top evenly with crumb topping
Bake pie for about 40 minutes or until crust is golden brown and topping is cooked.
Cool thoroughly, preferably overnight, so pie sets properly