Soft, spongey vanilla cupcakes are filled with sweet pastry cream and topped with homemade chocolate ganache frosting. Boston cream pie cupcakes are tasty, impressive desserts that you'll love serving!
Add the sugar, cornstarch, and milk to a large saucepan and mix until smooth. Cook, stirring continuously, over medium heat until mixture begins to thicken and boil. Reduce heat to medium and simmer for 1 minute. Remove from heat.
¼ cup granulated sugar, 1 tablespoon cornstarch, 1 cup milk
Add a little bit of mixture to the egg yolks and whisk together, then add egg mixture to milk mixture.
2 egg yolks
Place the saucepan back on the heat and bring to a light boil. Allow to boil for 2 minutes, stirring continuously.
Remove from heat and add the butter and vanilla. Stir until smooth. Set aside to cool to room temperature.
1 tablespoon unsalted butter, 1 teaspoon pure vanilla extract
For the Vanilla Cupcakes
Preheat oven to 350°F. Line a 12-count cupcake tin with cupcake liners.
Whisk together the flour, baking powder, and salt. Set aside.
1¼ cups all-purpose flour, 2 teaspoons baking powder, ½ teaspoon kosher salt
In a large bowl, using a hand mixer, beat the butter and sugar together until light and fluffy.
6 tablespoons unsalted butter, ¾ cup granulated sugar
Stir in buttermilk and vanilla extract.
6 tablespoons buttermilk, 1 teaspoon pure vanilla extract
Add egg whites and mix until well combined.
3 egg whites
Add half of the dry ingredients to the batter and mix until well combined. Mix in the milk. Add remaining dry ingredients and mix until well combined.
6 tablespoons milk
Fill the cupcake liners about halfway. Bake for 15 minutes, or until a toothpick inserted into the center comes out clean. Allow to cool completely on a cooling rack.
For the Chocolate Ganache Frosting and Assembly
Combine the chocolate chips and heavy cream in a microwave-safe bowl. Microwave in 15-second intervals until the chocolate is completely melted. Sift in powdered sugar and allow to cool for about 10 minutes.
½ cup semisweet chocolate chips, ¼ cup heavy cream, 2 tablespoons powdered sugar
Once everything is cooled and ready, cut out the centers of the cupcakes. Fill in the centers with pastry cream. Top the cupcakes with the chocolate ganache.
As tempting as it may be to skip making the homemade pastry and use instant pudding mix instead, DON'T do it! I promise, the classic cream filling of a real Boston cream treat is far better than instant pudding.
If you try to coat the cupcakes in ganache while it's too warm, it won't work out so well. The chocolate ganache needs about 10-15 minutes to cool, creating a deliciously thick texture.
Don't try to freeze these cupcakes. Sadly, the cream filling doesn't hold up well when frozen.
Storage: Store Boston cream pie cupcakes in an airtight container in the refrigerator for up to 4 days.