Makes 8 to 10 servings
8 ounces raw pistachios
For the génoise
3 ounces semisweet chocolate
3 tablespoons unsalted butter
1/3 cup unsifted cake flour
1 tablespoon granulated sugar
1/4 teaspoon baking powder
2 large eggs, room temperature
2 egg yolks, room temperature
1/4 cup granulated sugar
1 teaspoon vanilla
For the Pistachio Bavarian Cream
4 ounces pistachio nuts (from above)
2 cups milk
3 tablespoons water
2 teaspoons gelatin
1 cup heavy cream
1/4 teaspoon almond extract
4 large egg yolks
1/2 cup granulated sugar
1 tablespoon cocoa powder, optional
Prepare the pistachios
1. Bring 1 1/2 cups water to a boil, pour in the pistachio nuts (4 ounces from the recipe for Bavarian cream and 4 ounces from the ingredients for the decoration), and bring just to the boil. Immediately pour the nuts into a sieve and shake to remove as much moisture as possible. The skins slip off easily while the nuts are moist and warm. Set aside half the nuts.
2. Place half the blanched nuts on a baking sheet and allow them to air-dry for 3 hours or as long as overnight. Then place in a preheated 300°F (175°C) oven to roast them slightly, enhancing their flavor but without coloring them (about 5 to 10 minutes). Remove from oven. When the nuts are cool, grind them to the consistency of cornmeal. Set aside until time to decorate the dessert.
Make the génoise
3. Position rack in lower third of oven; preheat oven to 350°F (175°C). Using a paper towel, grease the bottom and sides of an 8-inch springform pan with solid shortening. Dust generously with all-purpose flour, tilt to coat, tap out the excess, and insert a parchment or waxed paper liner.
4. Chop the chocolate into matchstick-size pieces and place them with the butter in a 1 1/2-quart mixing bowl that fits snugly over another bowl half-filled with hot (140°F) water. (The water temperature can be this high because the addition of butter reduces the risk that the chocolate will scorch.) Stir occasionally until the mixture is melted and smooth; remove from the water; set aside to cool slightly.
5. Pour the flour, 1 tablespoon sugar, and baking powder in that order into a triple sifter. Sift onto a sheet of waxed paper to distribute the ingredients evenly; set aside.
6. Place the eggs and egg yolks in the bowl of a heavy-duty mixer. Add the 1/4 cup sugar and whisk ingredients by hand to combine. Rest the bowl in a shallow pan, such as a 10-inch skillet, filled with 1 inch of hot tap water (120°F). To prevent the eggs from setting, whisk them continuously for about 30 seconds, or until the mixture has warmed to body temperature, taking care that the temperature doesn’t exceed 110°F. Rub a little of the mixture between your thumb and forefinger; it should feel smooth, not granular.
7. Place the bowl on the mixer, and with the whisk attachment, whip the mixture on medium speed (#5) until it has cooled and thickened, appears paler in color and resembles a whole-egg meringue, and has tripled or more in volume (about 3 minutes). Add the vanilla toward the end of whipping. Test if it’s time to fold in the flour by lifting the whisk. If some of the mixture falls back into the bowl in ribbons and remains on the surface, proceed. But if it sinks back into the batter right away, continue whipping for a few more minutes, or until the desired consistency is achieved. Remove the whisk and bowl from the mixer.
8. With the aid of a flexible metal icing spatula, scoop one-third of the flour mixture and sprinkle it over the top. Using a rubber spatula, fold into the batter just until incorporated. Fold in the remaining flour in two more additions. With the aid of a rubber spatula, gently pour one-third of the batter onto the chocolate mixture, and fold until combined. Now pour the rest of the batter onto the chocolate mixture and fold together until combined.
9. Gently pour the batter into the prepared pan, taking care not to deflate the foam structure you’ve created. With the rubber spatula, level and smooth the surface. Bake for 20 to 23 minutes, or until the top springs back slightly when lightly touched and the sides begin to contract from the pan. Do not overbake.
10. Place the cake on a rack to cool for 5 to 10 minutes. With mitts, tilt the pan, and gently tap it to see that it has contracted from the sides. If not, or if in doubt, run a small metal spatula or the thin blade of a table knife between the outside cake edge and the metal rim, freeing the sides and allowing air to get under the layer as it is rotated. Then release and remove the outside of the springform pan. Allow to cool completely on rack.
11. When the cake is cool, cover it with another cooling rack, invert it onto the rack, and carefully remove the springform bottom from the cake. Slowly peel off parchment liner, turn it over so that the sticky side faces up, and reposition it on top of the cake. Cover with the first rack, invert the layer right side up, and remove the top rack.
Make the Bavarian cream
12. Rest a sieve on top of a 3-quart mixing bowl to strain the filling after it has been cooked.
13. Combine the milk and ground pistachios in a 1 1/2-quart saucepan and bring just to a boil over medium heat. Remove from the heat and let steep for 10 to 15 minutes. Pour through a second sieve to strain; extract milk from the nuts by pressing them against the sides of the sieve with a rubber spatula. Discard the nuts (their flavor is now in the milk) and measure the flavored milk, adding more milk if needed to make 1 1/2 cups.
14. Pour the water into a small bowl, sprinkle the gelatin over it, and set aside until softened.
15. Pour the cream and almond extract into a 1 1/2-quart deep mixing bowl, and with an electric hand mixer, whip the cream on medium to high speed (#8 to #10) until peaks barely form. Refrigerate until ready to use.
16. Whisk the egg yolks in a 1-quart mixing bowl to combine, add half the sugar, and whisk until completely incorporated.
17. Return the pistachio-flavored milk with the other half of sugar to medium heat and bring just to a boil. Remove from heat and pour about half into the egg mixture, whisking until blended. Pour mixture back into saucepan, whisk, and return to medium-low heat. Cook the mixture, stirring constantly with a wooden spoon, until it registers 165 to 170°F (71 to 79°C) on the candy thermometer and is thick enough to coat the back of the spoon (about 45 to 60 seconds).
18. Immediately remove from the heat and pour the mixture through the sieve into the mixing bowl. Add the gelatin; stir to dissolve; then set over a larger bowl of ice water. Stir the mixture occasionally to distribute the cold and prevent any lumpiness. When the mixture is syrupy and cooler than room temperature (about 8 to 10 minutes), fold in the chilled, lightly whipped cream with a rubber spatula until combined. If it goes beyond the syrupy stage and develops more body than desired, remove from the cold-water bath and whisk partially setting mixture until smooth. Then fold in the cream.
19. Pour into a container refrigerate for at least 4 hours or until cold and set.
Assemble the cake
20. Lightly oil the inside rim of the springform pan to facilitate the dessert’s removal. Trim 1/2 inch from the cake’s edge, using a small paring knife. Place a round of parchment or waxed paper inside the pan and center the génoise on it (this will make it possible to remove the dessert from the metal disk to a serving plate later).
21. The springform pan may leak, so place it on a baking sheet. (Once assembled, the dessert will go into the freezer for a short time to hasten the setting of the cream, so be certain the baking sheet fits in your freezer.)
22. Pour Pistachio Bavarian Cream into the springform pan, being certain that the gap between the trimmed cake and pan is filled, thus completely covering the génoise. The filling will come 1 inch below the springform’s top rim. Place the dessert in the freezer for 30 minutes to hasten the chilling and setting of the Bavarian cream. Cover the top of the pan with foil. Then refrigerate for at least 6 hours or preferably overnight.
Serving the cake
23. Up to 6 hours before serving, remove the dessert from the refrigerator and pat a damp sponge all around the outside of the pan. The moisture from the sponge will begin to loosen the Bavarian cream from the inside of the pan. Carefully and slowly release the springs on the pan to unmold. If the springs are stubborn, coax them with a thin-bladed knife around the edges.
24. Place the reserved ground dried pistachios on a baking sheet. Hold the dessert in one hand directly over the nuts. Tilt the cake slightly. With the other hand, pick up the ground nuts, and gently press them onto the sides and top of the Bavarian cream. Rotate the cake as you work until all the cream is covered. Press lightly with the side of a clean flexible metal icing spatula to ensure that the nuts adhere neatly. Alternately, coat only the sides of the Bavarian Cream with the ground nuts.
OPTIONAL DECORATION PREPARATION
If desired, make a template for a finishing touch: Buy acetate from an art supply store. (The joy of an acetate template is that it is reusable. To clean, run under water and pat dry.) Trace the letter P from an art book, newspaper, etc., with a pencil or felt pen. Cut it out, using a utility knife. The thinner the acetate, the easier it is to cut. The thicker it is, the easier it is to lift it from the cake after using.
If using the P template, center it on top of the cake. Pour the cocoa into a sieve. Using the palm of your hand for better control of the powder’s flow, gently tap the sieve to sprinkle it evenly over the P. Carefully lift the template. Then slip under the paper a large, wide spatula and transfer the dessert onto a serving plate. Refrigerate until 15 to 30 minutes before serving.
Adapted from Flo Braker, The Simple Art of Perfect Baking (Chronicle, 2003)