Boston Cream Pie Cupcakes

This is my mom's and aunt's favorite birthday cake.  My mom and aunt are twins and they are the best!  It is their birthday on the 13th.  So happy birthday Mom and Aunt Leslie.  I wish you guys could have eaten my Boston Cream Pie Cupcakes but come visit me and I'll make you some.  I love you both!

Boston cream pie is great.  First off, it isn't pie at all.  It is a delicious custard filled cake with chocolate ganache.  It is a little fancier than your average birthday cake and it is a little bit more difficult, but well worth it.

I usually don't like white cake.  With all the delicious things to back out there, white cake always seems boring and too sweet.  Not at all satisfying.  But this cake is a rich vanilla batter that is moist and dense and blows other white cakes out of the water.

I made these cupcakes for our intern Drew, who is moving back to Boston (get it, Boston Cream Pie, I'm so witty).  I'm hoping to bribe him to come back to our team when he graduates.  I've also been wanting to experiment with making this cake in cupcake form because Mom and Leslie love it so much.  Cupcakes are a way easier way to carry and serve this cake; I think it would be too messy to bring into the office otherwise.  However, the custard was really localized to just the center, so there were too many bites with just cake (delicious as it is) and no custard.  A bit disappointing, that.

I think custard is pretty scary for some people.  I don't mean people are having nightmares about custard (I don't know though, custard monsters maybe) but just it is intimidating.  There are some things that can go wrong and ruin a perfectly good custard but homemade custard is one of the joys of the world so I encourage everyone to get over their fears and with a few tips it is almost as easy as making it from the box and so much more delicious.

One thing you don't want to do is add egg yolks to a pan of simmering milk.  The egg yolks cook too fast and it gets lumpy.  You also don't want to heat the milk to fast, it will scald and form a skin on the pan which will make lumps, and can even burn and ruin your custard.  Cook it over a lower heat and keep whisking.  Even to me it always seems like nothing is happening and it is going to take forever but then once it gets going it goes quickly.

This recipe calls for you to strain your custard, so even if yours is a little lumpy no one will ever know.  Another good trick I learned from this recipe is when you chill the custard, cover it with plastic wrap that is actually touching the custard, don't leave any room for air.  Air unter the plastic wrap with form a skin on the custard which is icky.

I am giving you the recipe for the cake, because I see that as the proper version of it (from my family recipe cookbook).  The cupcakes are an easy variation.  The recipe made 12 cupcakes and they cooked for the same time (check after the shortest time).  I used a sharp knife to cut cylinders out of the center (which I ate) and then filled them with custard, as shown below.

I also like to make this in a bundt pan (the original recipe uses a springform pan).  One thing with a bundt ban is that there is more area for the custard to ooze out.  To prevent too much custard loss, I like to cut a trough in the bottom half of the cake for the custard to go in.  I think it looks so elegant when you drizzle the chocolate over it.  Make sure you cool the chocolate a bit before using it though, you want it to drizzle down the sides but you want most of it to stay on top.

Boston Cream Pie Cupcakes

CUSTARD
1 1/3 cups milk, divided
1 vanilla bean, split lengthwise or a tsp vanilla extract
1/3 cup sugar
2 tbsps cornstargch
3 large egg yoks
2 tbsps butter, cut up
CAKE
2 cups flour, not self-rising
2 tsps baking powder
1/4 tsp salt
1/2 cup butter, softened
1 cup sugar
2 large eggs at room temperature
1 tsp vanilla or vanilla bean
CHOCOLATE GANACHE
1 cup whipping cream
8 oz bittersweet or semi-sweet chocolate, chopped
1. Make custard: Combine 1 cup milk and vanilla in microwave proof bowl. Microwave on High 1 minute, until milk is hot. Whisk sugar and cornstarch in a two quart saucepan until blended. Whisk in remaining 1/3 cup milk and egg yolks until smooth.
2. If using a vanilla bean, remove vanilla bean from milk and scrape seeds into mixture in saucepan (discard bean). Gradually whisk hot milk into saucepan.
3. Cook custard over medium low heat whisking gently until it comes to a full boil. Reduce heat and boil for one minute, whisking gently. Remove from heat and stir (not whisk) in butter until melted. Strain custard through a sieve into a medium bowl. Cover surface directly with plastic wrap. Refrigerate 2 hours until cold. (Can be made ahead. Refrigerate overnight. To proceed with recipe, stir custard until smooth.)
4. Make cake: Beat butter in a large mixer bowl until softened, about 1 minute.  Gradually beat in sugar, then beat 4 to 5 minutes, until fluffy.  At low speed, beat in eggs one at a time until well blended.
5. Add milk, vanilla, flour, baking powder and salt and mix very slowly until just blended. 
6. Spread batter into a greased and floured pan, either an 9" springform pan or a bundt pan.  Bake in a 350F degree oven for 35 - 40 minutes or until a toothpick inserted in the center of the cake comes out clean.
7. Cool cake in pan about 10 minutes.  Run knife around side of pan.  If using a springform pan, invert on a wire rack, remove bottom and flip again (so rounded side is up).  If using a bundt pan invert on wire rack and remove pan.  (Can be made ahead.  Wrap well and freeze up to two weeks.  Thaw at room temperature 2 hours.)
8. Make ganache: Bring cream to a simmer, do not scald.  Remove from heat and whisk in chocolate until melted and smooth.
9. Split cake in half horizontally with a long serrated knife.  Remove top.  Place bottom layer on cake stand or serving plate.  Spoon chilled custard on bottom layer and spread up to 1/2 inch from edge.  Top with remaining cake layer, cut side down.  Spoon glaze onto center of cake and spread evenly, allowing some to run down the sides.  Let stand until ganache is firm, about 30 minutes.

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