Boston Cream Pie
- 2 1/2 cups all-purpose flour
- 3 1/2 tsp. baking powder
- 1/2 tsp. salt
- 6 Tbs. (3/4 stick) unsalted butter,
at room temperature
- 1 2/3 cups sugar
- 1 cup milk
- 2 tsp. vanilla extract
- 3 eggs
For the pastry cream:
- 9 egg yolks
- 1/2 cup sugar
- Large pinch of salt
- 4 Tbs. cornstarch
- 1 vanilla bean
- 2 1/2 cups milk
For the glaze:
- 1/4 cup heavy cream
- 1 cup sugar
- 3/4 cup plus 1 Tbs. water
- 1/2 cup cocoa powder
- 1 1/2 tsp. powdered gelatin
Over a sheet of waxed paper, sift together the flour, baking powder and salt. Set aside.
In the bowl of an electric mixer fitted with the flat beater, beat together the butter and sugar on medium-high speed until light. Reduce the speed to low. In a small bowl, mix together the milk and vanilla. Add the flour and milk mixtures alternately in 3 separate additions, mixing well and scraping down the bowl after each addition. Increase the speed to medium and add the eggs one at a time, beating well after each addition.
Spread the batter in the prepared pan. Bake until a wooden skewer inserted into the center comes out clean, about 1 hour. Let the cake cool in the pan for 10 minutes. Run a knife around the inside edge of the pan and invert the cake onto a wire rack. Carefully peel off the parchment paper and let the cake cool completely.
To make the pastry cream, in a bowl, whisk together the egg yolks, sugar and salt, then whisk in the cornstarch; set aside. Using a small, sharp knife, cut the vanilla bean in half lengthwise and scrape out the seeds. In a heavy-bottomed saucepan over medium-high heat, combine the vanilla bean, seeds and milk. Cook until bubbles appear around the edges. Remove from the heat and slowly pour the milk mixture into the egg mixture, whisking constantly.
Return the mixture to the saucepan and set over medium-low heat. Cook, stirring constantly, until the mixture is as thick as mayonnaise, 5 to 7 minutes. Remove from the heat and strain the pastry cream into a clean bowl; discard the vanilla bean. Cover with plastic wrap directly on the surface of the pastry cream. Let cool completely, then refrigerate until ready to use.
To make the glaze, in a saucepan over medium-high heat, stir together the cream, sugar, the 3/4 cup water and the cocoa. Bring to a boil, whisking often, then reduce the heat to low. Simmer, stirring often, until the glaze thickly coats the back of a spoon, 10 to 12 minutes. Remove from the heat and pour the glaze into a bowl. Let cool.
Meanwhile, in a small bowl, stir the gelatin into the 1 Tbs. water and let stand for 2 minutes. Place the bowl of gelatin over a small saucepan of barely simmering water, stirring until it is liquid and translucent. Whisk the gelatin into the glaze. Refrigerate, stirring occasionally, until the glaze has a thick pouring consistency, 30 to 60 minutes.
To assemble the cake, cut the cake in half horizontally. Place the base of the cake on a large rimmed plate; spread the pastry cream on top of the bottom layer. Place the second layer on top and press gently. Drizzle the glaze over the top of the cake, letting it drip down the sides.
Refrigerate the cake until almost ready to serve. Let stand at room temperature for 20 minutes before serving. Cut slices with a serrated knife. Serves 8 to 10.
Adapted from Williams-Sonoma TASTE Magazine, "Layers of Delight," by Emily Luchetti (Spring 2002).