Individual Boston Cream Pies in a Jar
Prep time: 
Cook time: 
Total time: 
Yield: 11 individual cakes
 
Creamy custard is baked in individual jars with a light vanilla butter cake on top, and then topped with dark chocolate ganache and white chocolate buttercream for a fun spin on a classic Boston Cream Pie.
Ingredients
Custard:
  • 1 large egg
  • 3 large egg yolks (you’ll use the whites in the cake)
  • 1 tablespoon pure vanilla extract
  • 3 cups milk (I used 2%)
  • ½ cup sugar
  • ⅓ cup all-purpose flour
  • ⅛ teaspoon salt
  • 3 tablespoons unsalted butter
Cake:
  • 4 tablespoons unsalted butter, melted and cooled slightly
  • 2 large eggs
  • ¾ cup sugar
  • 1½ teaspoons pure vanilla extract
  • ¼ cup milk (I used 2%)
  • 1 cup all-purpose flour
  • ¾ teaspoon baking powder
  • ¼ teaspoon salt
  • 3 large egg whites (you’ll use the yolks in the custard)
Dark Chocolate Ganache:
  • 8 oz good-quality bittersweet or semi-sweet chocolate, chopped
  • 2 tablespoons unsalted butter
  • 2 tablespoons milk (I used 2%)
  • ½ teaspoon pure vanilla extract
White Chocolate Buttercream:
  • 4 oz (about ⅔ cup chopped) white chocolate, chopped
  • 3 tablespoons unsalted butter, at room temperature
  • 6 tablespoons vegetable shortening, at room temperature
  • 1½ teaspoons pure vanilla extract
  • ¾ lb powdered sugar
  • 2-4 tablespoons milk (more or less to achieve desired consistency)
Other:
  • Butter, to grease the jars
Instructions
  1. Preheat oven to 350F; grease 11 (8 oz) jelly jars with butter.
  2. For the Custard: Whisk together the egg, egg yolks, and vanilla in a medium bowl and set aside. Whisk together the milk, sugar, flour, and salt in a medium saucepan; bring to a gentle boil over medium heat, stirring occasionally. Turn off the heat and very slowly ladle the hot milk mixture into the egg mixture while whisking, adding just a drop at a time at first, and then whisk in the butter. Strain the custard through a fine mesh sieve to remove any lumps. While it’s still hot, slowly pour the custard into the prepared jars, being careful not to splash the sides of the jar. Cool the custard a bit (so that it’s set) before you pour the cake batter on top.
  3. For the Cake: While the custard cools, make the cake batter. Whisk together the butter, eggs, sugar, vanilla, and milk in a large bowl. In a separate bowl, whisk together the flour, baking powder, and salt. In another bowl, whip the egg whites to stiff peaks. Whisk the dry ingredients into the wet, then fold in the egg whites, ⅓ at a time. Carefully spoon the batter onto the set custard (you can use a small ladle or put the batter into a pastry bag and pipe it).
  4. Arrange the jars (so that they don’t touch each other or the sides of the pan) in a large, deep roasting pan; add enough hot (not boiling) water to come up to the top of the custard (but not the cake batter). Bake until the cake is light golden on top and a toothpick inserted into the cake inside comes out clean or with just a couple crumbs, about 45 minutes. Cool completely before proceeding.
  5. For the Dark Chocolate Ganache: Melt the chocolate and butter together in a microwave or double boiler; add the milk and vanilla and stir until smooth. Spoon over the cooled cakes, and let the chocolate set before piping the White Chocolate Buttercream on top.
  6. For the White Chocolate Buttercream: Melt the white chocolate in a microwave or double boiler. Beat together the melted chocolate, butter, shortening, and vanilla. Slowly beat in the powdered sugar; while still beating, add the milk a little at a time until the frosting reaches your desired consistency. Pipe the frosting on top of the cakes once the ganache is set.
  7. Serving and Storing: Serve these within 1 to 2 hours of having them fully assembled. Otherwise, you can make them up to 3 days ahead of time; store them in the fridge and let them sit at room temperature for about 20 minutes before serving.
Notes
To Make in Advance: These cakes can be made up to three days ahead of time; store them in the fridge and let them sit at room temperature for about 20 minutes before serving.
Recipe by An Edible Mosaic™ at https://www.anediblemosaic.com/individual-boston-cream-pies-in-a-jar/