A chocolate shortbread crust makes for an indulgent change from a classic tart shell. Filled with a creamy pistachio mousse, this dessert is one that we always recommend for a party.
To make the crust: Mix all of the ingredients together until smooth. Press into the bottom of a lightly greased 9" springform pan or 9" pie pan. Prick all over with a fork, then freeze for 30 minutes.
While the crust chills, preheat the oven to 400°F.
Bake the chilled crust for 15 to 18 minutes, until set and no longer wet-looking in the center. You should smell chocolate when it's done. Remove from the oven and let cool completely.
To make the filling: Combine the eggs, egg yolks, and confectioners' sugar in a heatproof bowl.
Place the bowl over simmering water and beat until thickened and the temperature reaches 165°F when measured with a digital thermometer.
Remove from the heat and stir in the pistachio paste until evenly combined.
Place the bowl in a pan of ice water to cool, stirring occasionally.
In a separate bowl, whip the heavy cream to medium peaks, then fold it into the cooled pistachio mixture.
Scoop the filling into the cooled crust and smooth the top.
Freeze for 6 hours before serving.
To serve: Run a thin spatula around the outside edge of the cake to separate it from the side of the springform pan (if using), then release the springform clip. Remove the side of the pan and sprinkle chopped pistachios on top before slicing.
Store covered and frozen for up to 2 weeks.
Want to make your own pistachio paste? The following recipe makes 1 generous cup of paste; use what you need in the recipe and refrigerate or freeze the rest.
1 1/3 cups (160g) shelled roasted pistachios, salted or not
6 tablespoons (74g) granulated sugar
4 to 6 tablespoons (57g to 85g) water
Blanch the nuts in boiling water for 15 to 20 seconds, then drain and rinse with cold water. Rub the nuts between layers of a clean dish towel; the friction will loosen the nuts’ skin, making them easier to peel. Peel the skin from the nuts.
Pulse the pistachios and sugar in a food processor until no large bits of pistachios are visible (the finer the grind, the smoother the finished paste will be).
Add 4 tablespoons (57g) water and pulse to combine. Add more water if necessary to make a smooth paste.
Store paste airtight in the refrigerator.
Note: Blanching and peeling the nuts results in a bright-green paste that looks great in your baked goods. Skipping this step yields a muddy brown paste that’s not as attractive; that said, feel free to skip those extra steps if the paste’s color won’t bother you.
