***Crust*** 1 cup all purpose flour 1/2 cup unsweetened cocoa powder 3 Tbsp sugar 1/4 tsp salt 1/2 cup (1 stick) butter, cut into pieces and chilled 1 large egg yolk 3 Tbsp cold water
***Filling*** 1 envelope unflavored gelatin 2/3 cup sugar, divided 1/8 tsp salt 1/3 cup water 3 large egg yolks 2 tsp vanilla extract 1 1/4 cups heavy cream 3 large egg whites 1 Tbsp espresso powder, dissolved in 1 Tbsp water Chocolate shavings (dark, semi-sweet, marbled), for garnish
Using a pastry cutter or food processor, cut in the cold butter pieces into the flour mixture until course crumbs form. Add egg yolk and the cold water, and mix (don't knead) until the dough comes together. Transfer dough to a sheet of plastic wrap, shape into disk, and wrap and refrigerate for 30 minutes until firm. 2. Once dough is chilled, heat oven to 425 degrees F. Lightly grease a 10-inch pie plate. 3. Roll out dough between 2 sheets of plastic wrap into 14-inch circle. Remove top sheet of wrap, invert crust into pie plate and remove the other wrap. Gently press crust over bottom and up the sides of pie plate. Crimp the edge of crust, prick all over with fork, and place in freezer for 10 minutes to firm.
4. Line crust with foil, fill with dried beans or pie weights. 5. Bake in 425 degrees F oven for 10 minutes. Remove from oven, remove foil & pie weights. Return crust to oven and bake for another 8-10 minutes until set and dry. Let cool in plate. 6.Filling:In small saucepan, stir together gelatin, 1/3 cup sugar, salt, water, and yolks. Let stand for gelatin to soften, about 3 minutes. Heat over medium-low heat, whisking gently, until mixture is slightly thickened, at about 160 degrees F, or after about 6-8 minutes.
Strain mixture through fine-mesh sieve into large bowl. Stir in vanilla and refrigerate for 5 minutes. 7. In another large bowl, beat cream until soft peaks form, and refrigerate. 8. Remove the gelatin mixture from refrigerator and whisk slightly and let stand at room temperature. 9. In a medium bowl, beat egg whites until foamy. Gradually add remaining sugar until shiny, stiff peaks form. 10. Fold beaten egg whites into gelatin mixture, then fold in chilled whipped cream. 11. Remove 1 1/2 cups of mixture to small bowl and fold in dissolved coffee. Dollop 1 cup of this coffee-flavored chiffon mixture to the cooled pie crust. 12. Top with vanilla chiffon. Place small dollops of the remaining coffee-flavored chiffon on top, swirl with thin knife or spatula to marbleize chiffon. Refrigerate, covered, until filling is set, about 2 hours. 13. Before serving, garnish with chocolate curls.