Boston Cream Pie, despite its name, is not a pie at all. Boston Cream Pie is a layer cake that is filled with pastry cream and topped of with an indulgent chocolate glaze. The dessert is said to have been created at Boston’s Parker House Hotel in 1856, and it has been popular ever since – even becoming the official dessert of the state of Massachusetts! It is popular not only because all of the components are so good together, but because the dessert is very unique and you won’t find many other cakes – or pies, for that matter – like it.
The cake for a Boston Cream Pie is usually a yellow sponge cake, chiffon cake or butter cake. It should have a slight yellow color and a slight vanilla flavor, but many chefs will simply use their favorite type of cake rather than sticking to the most traditional sponge cake option. I like to use a yellow butter cake for my Boston Cream Pie. This cake has a nice vanilla flavor to it, and it is very moist and tender. The cake goes very nicely with the creamy vanilla pastry cream in between the cake layers and stands up to the chocolate glaze, too.
The vanilla pastry cream is similar to vanilla pudding, and is made in much the same way on the stovetop. It has a thick consistency so it will hold up to spreading and slicing without running out of the cake. My version has a great vanilla flavor, thanks to some generous use of fresh vanilla beans, and is good enough that you can eat it on its own. It does need to be prepared in advance and completely cooled before using, so start your recipe preparation by making the filling and then moving on to the other components. The pastry cream can also be made a day or two ahead and stored in the refrigerator.
Just as the cake used in Boston Cream Pie varies, so does the chocolate glaze on top. I’ve had thin, almost watery chocolate glazes that only add a little flavor, and I’ve had thick heavy glazes that dominate the cake. My glaze is a very simple ganache made with dark chocolate and butter. It has a dark chocolate bite to it, but it doesn’t overwhelm the other flavors in the cake. The glaze should really only be spread on top of the cake for this recipe, not used to cover the whole thing. The glaze goes onto the cake shiny, but it will set up firmly within an hour or so, which makes slicing the cake much neater and easier.
This cake is excellent when it is fresh, but is also good a day or two after being made, when the layers have had a chance to meld together. It’s a very classic American dessert and a huge crowd pleaser. The recipe below covers the cake, the filling and the glaze for this cake. The pastry cream recipe is very generous because it never hurts to have extra pastry cream, and this allows you to use as much, or as little, filling as you like when you stack up your very own Boston Cream Pie.
Boston Cream Pie
1 3/4 cups cake flour
1 1/3 cups sugar
1 tsp baking powder
1/2 tsp baking soda
1/2 tsp salt
1/2 cup butter, room temperature
1 large egg
2 egg yolks
1 cup buttermilk
1 1/2 tsp vanilla extract
1 1/2 cups pastry cream (recipe below)
1 recipe for chocolate glaze (recipe below)
Preheat oven to 350F. Lightly grease a 9-inch round cake pan and line it with parchment paper.
In a large bowl, or the bowl of an electric mixer, sift together flour, sugar, baking powder, baking soda and salt.
Cut butter into 4 or 5 chunks and drop into the bowl with the flour mixture. Blend on low speed until mixture looks sandy and no large chunks of butter remain, 1-2 minutes.
In a large measuring cup, combine egg, egg yolks, buttermilk and vanilla extract. Beat lightly with a fork until combined. With the mixer on low, pour 1 cup of the buttermilk mixture into the bowl. Turn speed up to medium and beat for 1 1/2 minutes. Reduce speed back to low and pour in the rest of the buttermilk mixture. Continue to beat at low speed for an additional 30 seconds, until liquid is fully incorporated. Scrape down the sides of the bowl and beat for a few more seconds, if necessary. No streaks of dry ingredients should remain.
Pour batter into prepared pan.
Bake for 40-45 minutes, until a toothpick inserted into the center of the cake comes out clean, and the cake has begun to pull slightly away from the sides of the pan.
Turn cake out onto a wire rack to cool completely and peel off parchment paper.
When cake has cooled completely, use a large serrated knife to cut the cake in half to create two equal cake rounds. Place one cake round onto a cake plate or serving platter.
Top cake round with approx 1 1/2 cups vanilla pastry cream (recipe below) and spread into an even layer. Top with second cake round.
Prepare chocolate glaze and, when the glaze is still warm, pour it onto the top of the cake. Use an offset spatula to spread it to the edges, allowing the glaze to drip down the sides of the cake.
Allow glaze to set before serving.
Cake should be stored in the refrigerator.
Vanilla Bean Pastry Cream
2 cups low fat milk
1/2 vanilla bean
2 large eggs, at room temperature
2 large egg yolks, at room temperature
1/2 cup sugar
1/3 cup cornstarch
In a medium saucepan, combine milk and vanilla bean. Bring to a simmer over medium heat then turn off heat. Scrape vanilla bean into milk.
While milk is cooking, combine eggs, egg yolks and sugar in a large mixing bowl. Beat until smooth, then add cornstarch and beat until smooth again. When the milk is done, pour a few tablespoons of milk into the egg mixture while whisking constantly. Repeat this a few times until about half of the milk has been added. It is important to add the hot milk slowly (tempering) so you do not cook the eggs.
Add the remaining milk and return the whole mixture to the sauce pan. Cook, stirring constantly, over medium heat until the custard thickens – about 3-5 minutes.
Strain through a sieve into a medium bowl, cover surface of the pastry cream with plastic wrap and chill completely. Pastry cream will thicken more as it cools.
Note:You may not need all of this pastry cream for your Boston Cream Pie, although you can add more to make the custard layer thicker. Leftover pastry cream can be stored in the refrigerator for several days and served with fruit or other desserts.
3/4 cup chopped dark chocolate or chocolate chips
1/4 cup butter
1 tsp vanilla extract
In a microwave safe bowl, melt chopped chocolate (or chocolate chips) and butter together. Whisk until smooth, then whisk in vanilla. When glaze is smooth, pour it onto the top of the cake, and use an offset spatula to spread it to the edges, allowing the glaze to drip down the sides of the cake.