JULIA'S CHOCOLATE TART DOUGH

Steps:

• To make dough in food processor fitted with metal blade: put the flour, cocoa, sugar and salt in work bowl and pulse just to blend.
• Add butter and pulse 8-10 times, until pieces are about the size of small peas.
• With machine running, add yolk and ice water and process, in short bursts, until JUST crumbly- don't overwork it!
• Turn it out onto the work surface and, working with small portions, smear the dough across the surface with the heel of your hand.
• Gather the dough together and shape it into a rough square.
• Pat it down to compress it slightly, and wrap in plastic.
• Chill until firm, at least 30 minutes.
• The dough can remain in the refrigerator for 3 days, or it can be wrapped airtight and frozen for a month.
• Thaw the dough, still wrapped, overnight in the refrigerator before rolling it out.
• Cook's note: When I made this, I stuck the dough in the freezer to chill, then promptly forgot about it.
• 4 hours later, when I remembered to pull it out, it was frozen solid.
• I pulled out my box grater and grated it directly into the pie pan.
• It worked beautifully, no roling involed: just patted it all down into place.