This cake (pie!) I baked for my friend Kristin. Long ago last year, we agreed to trade two pies of her choice for a hat of my choice. Without a single doubt I got the better of this deal. Kristin’s first choice was a pie delivered last fall, pre-hat. This is her second and final payment on our barter, and in celebration of her birthday (belatedly).
In all my years of baking, I had never prepared a Boston Cream Pie. I had a vision in my head of…. well, a cream pie. It is not. So – I spent a couple days looking at recipes in my old books, which is typically how I start with a new project. The Boston Cream Pie is basically a sponge cake filled with a custard and topped with a ganache, but the ganache is specifically more like a glaze in that it does not harden. This is accomplished with a small twist on the classic ganache. There were some variations in the cake recipes but several sources indicated: simply go with your favorite sponge cake recipe. And that’s what I did, my favorite sponge cake recipe is a tried & true yellow cake.
Boston Cream Pie
1 C Butter
1 – 1/2 C Sugar
8 egg yolks
3/4 C Milk
1 – 1/2 t Vanilla
2 C Cake Flour
2 t Baking Powder
1/2 t Salt
Preheat oven to 350 degrees. Grease and flour 2-8″ rounds. Sift together flour, baking powder and salt, set aside. Cream butter & sugar until light & fluffy. Beat egg yolks in, one at a time, and stir in vanilla. Alternately beat dry mixture in with milk until just incorporated. Pour into prepared pans and bake 25 – 30 minutes.
3 Large egg yolks
1/3 C Sugar
3 T Corn Starch
1 Pinch salt
1 1/2 C Milk
1 tsp Pure vanilla
Whisk egg yolks together lightly in a large bowl and then set aside. In a heavy saucepan, combine sugar, starch and salt. Whisk them together, and add 1/2 C milk and whisk until combined. Place saucepan over medium heat and slowly add remaining two cups of milk. Mixture will thicken and begin to boil in about 8 to 10 minutes. STIR CONSTANTLY. When thick, remove from heat. Take 1/4 C hot filling and dribble into egg yolks, STIRRING CONSTANTLY. Once eggs are tempered, pour them slowly back into the hot mixture and continue cooking on medium heat until bubbly and thick again. Remove pan from heat and stir in 1 T pure vanilla. (Did I mention, you need to stir this constantly!)
Chocolate Ganache Glaze:
4 oz Semi-sweet chocolate (I like to use Scharffen Berger)
1/2 C Heavy Cream
1 T Unsalted Butter
Chop your chocolate very finely. Don’t leave big chunks – this will be important later. Put in a heat proof glass bowl and set aside. In a heavy saucepan, heat your heavy cream and butter until just prior to boiling. Do not boil this – it will scald very easily. Once hot, pour over the top of your chocolate and stir. It will begin to melt and seem very disparate, but do not lose faith – keep stirring and it will suddenly pull together. Voila! Cool this prior to using on cake. Ganache I am familiar with does not have the butter typically, so this is the part that keeps the ganache from hardening in this particular cake.
Level your cake loaves first. This means set the sponge on a level surface, lean down and look at it from the side – and lop off with a serrated knife anything that is above the top rim of the cake. I have a small kitchen level which I use for this. Then, after leveling your two sponges, start by placing first sponge top down and cover with cooled custard. Place next sponge finished side up, and spoon on your cooled ganache, allowing it to drip down the sides.
Tempering egg yolks by pouring just a bit of custard into them and whisking quickly. This is an important step and will distinguish your custard from scrambled eggs!
Custard, finished, ready for vanilla
Finely chopped semi-sweet chocolate
This is the point at which a person may worry her ganache is a complete fail. Hang in there!