Pies and Tarts Galore!
Tart dough:
1 stick unsalted butter, softened
1 / 3 cup sugar
1 large egg yolk
1 cup flour
2 1 / 2 tablespoons unsweetened cocoa powder
Place the butter and sugar in a mixer stand and beat at medium speed for 3 minutes. The dough should be soft and creamy. Scrape the bowl with a spatula. If there are hard lumps of butter still visible, beat for another minute to melt completely in the mixture. Add the egg yolk and beat well. Scrape the bowl. In a medium bowl, whisk together the flour and cocoa powder. Toss in the butter all at once.Turn the mixer to lowest speed and mix until the dough barely meets and looks moist, with a dark solid. Scrape down the bowl. If there are patches of unincorporated flour, butter, finish mixing the dough by hand with a spatula. If you beat too long, you will have a smooth surface, pasta batterlike, which will be harder to press into the pan, because it is sticky. If this happens, chill the dough for 15 minutes before continuing....