Traditionally, Boston Cream Pie consists of a vanilla/yellow cake, pastry cream and a chocolate ganache. Because I wanted to decorate these as little bird’s nests, and wanted the nests to be clearly defined from the other glaze, I opted to use a dulce de leche (caramel glaze) instead of the chocolate ganache and then a chocolate butter cream for the nests.
for the Cupcakes
1 3/4 cups all-purpose flour
1 1/2 teaspoons baking powder
3/4 teaspoons table salt
1 cup granulated sugar
1 1/2 sticks unsalted butter, softened but slightly cool, cut into 12 pieces
3 large eggs
3/4 cups milk
1 1/2 teaspoons vanilla extract
For the Pastry Cream
1 1/2 cups heavy cream
3 large egg yolks
1/3 cup granulated sugar
pinch of table salt
4 teaspoons cornstarch
2 tablespoons unsalted butter, cold cut into 2 pieces
1 1/2 teaspoons vanilla extract
for the Dulce de Leche Glaze
1 quart whole milk
1 1/2 cups sugar, approximately 1 1/2 cups
1 vanilla bean, split and seeds scraped
1/2 teaspoon baking soda
for the Buttercream Frosting Bird’s Nests
1 1/2 cups confectioners’ sugar
1/4 cup butter, softened
1 pinch salt
1 1/2 (1 ounce) squares unsweetened chocolate, melted
1 1/2 tablespoons milk
1 teaspoon vanilla extract
1 bag Cadbury mini-eggs (the kind with a candy shell; alternatively, you can use peanut M&Ms)
For the cupcakes: Preheat oven to 350F. Line a standard muffin pan with paper baking cups and set aside.
In the bowl of a stand mixer, combine the flour, baking powder, salt, and sugar on low speed. Add the butter, 1 piece at a time, and combine until the mixture resembles coarse sand. Add the eggs, 1 at time, and mix until fully combined. Add the milk and vanilla, increase the speed to medium, and mix until the batter is light, fluffy and free of lumps.
Fill the lined muffin cups three-quarters full, being careful not to overfill. Bake until a toothpick inserted in the center of the cupcake comes out clean, about 18 to 20 minutes. Cool the cupcakes in the pan for 5 minutes, then transfer to a wire rack to cool completely.
For the pastry cream: Bring the cream to a simmer in a medium saucepan over medium heat, stirring occasionally. Meanwhile, whisk the yolks, sugar, and salt together in a medium bowl. Add the cornstarch and whisk the mixture is pale yellow and thick.
When the cream reaches a full simmer, slowly whisk it into the yolk mixture. Return the mixture to the saucepan and cook over medium heat, whisking constantly, until thick and glossy. Off the heat, whisk in the butter and vanilla. Transfer the pastry cream to a small bowl and refrigerate, with plastic wrap pressed flush against its surface, until cold and set, at least 2 hours.
For the glaze: Combine the milk, sugar, vanilla bean and seeds in a large, 4-quart saucepan and place over medium heat. Bring to a simmer, stirring occasionally, until the sugar has dissolved. Once the sugar has dissolved, add the baking soda and stir to combine. Reduce the heat to low and cook uncovered at a bare simmer. Stir occasionally, but do not re-incorporate the foam that appears on the top of the mixture. Continue to cook for 1 hour. Remove the vanilla bean after 1 hour and continue to cook until the mixture is a dark caramel color and has reduced to about 1 cup, approximately 1 1/2 to 2 hours. Strain the mixture through a fine mesh strainer. Let cool completely in the refrigerator.
For the buttercream frosting: In small bowl mix at medium speed (it is better to use a handheld mixer, not your stand mixer for this one), sugar, butter, and salt until light and fluffy. Add melted chocolate, milk and vanilla extract, beating until well blended. Refrigerate for at least a few hours; you want this to be as firm as possible.
To assemble: Insert a small knife at a 45 degree angle about 1/8 inch from the edge of each cupcake and cut all the way around, remove a cone of cake. Cut away all but the top 1/4 inch of the cone; leaving only a small disk of cake which will be used to top the cupcake. Fill each cupcake with 2 tablespoons of pastry cream and top with the disk of cake. Carefully top each filled cupcake with a 1-2 tablespoons of the dulce de leche glaze. Refrigerate until set, about 30 minutes. To make the bird’s nests, using a #3 tip, fill a pastry bag with the buttercream frosting. Create a ‘nest’ across the entire top of the cupcake (bottom and sides). Place 2-3 robin’s eggs in the nest. Refrigerate until ready to serve.