Place flour, cocoa powder, Clabber Girl Baking Powder and salt in the bowl of a food processor and process for a few seconds to combine.
Add the butter pieces to the flour mixture and process until the mixture resembles coarse meal, about 10 seconds
Add the ice water in a slow steady steam, pouring it through the feed tube with the machine running, just until the dough holds together.
Gather up the dough and form into a disc, wrap in plastic wrap and refrigerate until chilled but not hard, 1-2 hours.
On a lightly floured work surface, roll out the dough into a 1/8 inch thick round (rolling pin). Transfer to a 9-inch pie dish, trimming (paring knife) the excess dough around the rim ½ inch from rim, tuck in edges to make crust. Set in fridge until needed.