1 ½cups(213g)unbleached all-purpose flour (see note)
10tablespoons(142 )salted butter, frozen
½cup(113g)sour cream, not lowfat or light, plus an additional tablespoon or three if needed
In a medium bowl, lightly whisk together the flour, salt and sugar.
Using the large holes of a box grater, grate the butter into the dry ingredients.
With a fork, toss the butter and flour mixture until the butter pieces are all evenly coated with flour. Don't break down the butter pieces in this step, just lightly toss until they are coated with flour.
Spoon the sour cream into the bowl. Using the same fork, mix the sour cream into the butter/flour mixture by pressing the fork down into the sour cream in order to mash the large clumps of sour cream into the flour and butter. A commenter suggested using a pastry blender which will help incorporate the sour cream a bit better. The sour cream won't mix in like a traditional pie crust with ice water. But take care not to overwork the dough trying to get the sour cream mixed in - if the butter pieces get too small and overprocessed, the crust will be tough.
After a few turns with the fork, it is easiest to use your hands to pull the dough together. It will look a bit shaggy but as you press it together (quickly and firmly so the the butter pieces don't melt), it should start to form a cohesive ball.
If it still seems overly dry, add a teaspoon or so of sour cream at a time until it comes together.
It's ok if there are still a few dry spots or cracks in the dough. The mixture should not be overly wet or sticky. At the same time, it shouldn't be falling apart either. It should hold together when pressed (see the pictures below). Many of you have had to add quite a bit more sour cream. That's ok as long as the crust isn't overly saturated (then it will be dense and gummy). Much of that depends on how you measure flour - if you pack the flour into your measuring cup, you'll obviously need more sour cream (try to measure the flour with a light hand).
At this point the dough can be rolled out on a lightly floured counter or it can also be pressed into a flat disc and wrapped in plastic to be refrigerated for 1-2 days or frozen for up to a month.
To roll out, lightly flour your countertop and using firm, even strokes, roll from the center outward, turning the dough a quarter turn every few strokes. The less you mess with the dough the better - even rolling - so try not to overwork it. Roll it out to a thin crust as quickly as possible.
Roll the dough over the rolling pin and unroll it onto the pie plate. Gently lift up the edges of the pie crust and settle it into the bottom of the pie plate without pressing or smushing.
Trim the edges to within 1/4-inch. Fold the short overhang underneath the top edge of the pie plate and crimp all the way around.
Cover with plastic wrap and refrigerate for 30 minutes before using. To blind bake (prebake the pie crust), line the refrigerated crust with foil and fill with dry beans or pie weights. Bake at 350 degrees for 20-25 minutes. Gently remove the foil and beans/weights and return to the oven to bake for another 10-12 minutes until nicely golden.
Doubling: this recipe can be easily doubled for a double crust pie. Measuring the Flour: as I mentioned in the blog post above, be careful not to overmeasure the flour. I use the spoon and sweep method (normally I use the dip and sweep method for cookies and other recipes but it's very important in this recipe to not overflour or you'll have a bit of trouble with the recipe). I'll make sure I weigh the flour the next time I make it and report back for a more accurate measure.