Recipe: Boston cream cupcakes from Cook's Illustrated

My friend Emily is always baking up something delicious and beautiful. Emily often tries to encourage my baking endeavors with baking-themed birthday gifts, but this year Em forewent the gear and brought the goods. For my birthday earlier this month, she stopped by with some gorgeous little Boston cream cupcakes. It was love at first bite. Not too rich, not too sweet, and a perfect blend of crumby and creamy.

Ingredients:
Pastry Cream

• 1 1/3 cups heavy cream 
• 3 large egg yolks 
• 1/3 cup sugar 
• Pinch table salt 
• 1 tablespoon cornstarch plus 1 additional teaspoon 
• 2 tablespoons cold unsalted butter, cut into 2 pieces 
• 1 1/2 teaspoons vanilla extract

Cupcakes

• 1 3/4 cups all-purpose flour, plus additional for dusting muffin tin 
• 1 1/2 teaspoons baking powder 
• 3/4 teaspoon table salt 
• 1 cup sugar 
• 12 tablespoons unsalted butter (1 1/2 sticks), softened but still cool, cut into 12 pieces 
• 3 large eggs 
• 3/4 cup milk 
• 1 1/2 teaspoons vanilla extract

Chocolate Glaze

• 3/4 cup heavy cream 
• 1/4 cup light corn syrup 
• 8 ounces bittersweet chocolate , chopped 
• 1/2 teaspoon vanilla extract

Instructions:
1. For the pastry cream: Heat cream in medium saucepan over medium heat until simmering, stirring occasionally. Meanwhile, whisk egg yolks, sugar, and salt together in medium bowl. Add cornstarch and whisk until mixture is pale yellow and thick, about 15 seconds.

2. When cream reaches full simmer, slowly whisk it into yolk mixture. Return mixture to saucepan and cook over medium heat, whisking constantly, until thick and glossy, about 1 1/2 minutes. Off heat, whisk in butter and vanilla. Transfer pastry cream to small bowl, press plastic wrap directly on surface, and refrigerate until cold and set, at least 2 hours or up to 2 days.

3. For the cupcakes: Adjust oven rack to middle position and heat oven to 350 degrees F. Spray muffin tin with cooking spray, flour generously, and tap pan to remove excess flour.

4. With electric mixer on low speed, combine flour, baking powder, salt and sugar in large bowl. Add butter, one piece at a time, and combine until mixture resembles coarse sand. Add eggs, one at a time, and mix until combined. Add milk and vanilla, increase speed to medium, and mix until light and fluffy and no lumps remain, about 3 minutes.

5. Fill muffin cups three-quarters full (do not overfill). Bake until toothpick inserted in center of cupcake comes out clean, 18 to 20 minutes. Cool cupcakes in pan 5 minutes, then transfer them to rack to cool completely.

6. For the glaze: Cook cream, corn syrup, chocolate, and vanilla in small saucepan over medium heat, stirring constantly, until smooth. Set glaze aside to cool and thicken for 30 minutes.

7. Prepare and fill cupcakes (directions below). Refrigerate until just set, about 10 minutes. (Cupcakes can be refrigerated for up to 2 days; bring to room temperature before serving.)

Filling and glazing the cupcakes
1. Insert the tip of a small knife at a 45-degree angle about 1/8 inch from the edge of the cupcake and cut all the way around, removing a cone of cake.
2. Cut away all but the top 1/4 inch of the cone, leaving only a small disk of cake.
3. Fill the cupcake with 2 tablespoons pastry cream and top with the disk of cake.
4. Set the filled cupcakes on a wire rack set over parchment paper. Spoon 2 tablespoons of glaze over each cupcake, allowing it to drip down the sides.

Makes 12.

This recipe was adapted by Jessica Webster and originally posted on AnnArbor.com on Oct. 27, 2010.