Birthday cakes can be tricksy at times. You are trying to make something that both appeals to the person in question AND to the other guests AND to yourself (in this case). You don’t know if folks are wild about frosting, or prefer cake. What about ice cream ? Should candles grace the top ? Far too many questions. I’m already overwhelmed.
While I was home, my dad celebrated his birthday (he’s probably 21* now, quite the young’un). He notoriously doesn’t like to eat white sugar. Or chocolate. Or sweets in general when attempting to be healthy. However, I (being his daughter) know his weakness : Boston Cream Pie. When my sister and I were younger, he would sneak one out of Roche Bros. supermarkets as a treat or a fun dessert – which is how I came to know what Boston Cream Pie even was, for it is somewhat of an obscure dessert, with origins both in New York (for the original “pudding cake”) and in Boston (from the Parker House, which copied the NYC cake but topped it with chocolate glaze). A nice, light, vanilla sponge cake filled with rich vanilla cream and slathered with fine chocolate ganache, this is a surprising birthday gateau – no ice cream necessary and yes, the candles will stay on and no – there is NOT very much butter involved. It is surprisingly simple to make (once you get over the fact that yes, you need a billion eggs) but will take time and patience, for each component has to be done at a separate time. If you have a snow day to spent inside, give this “pie” a whirl !
Pastry Cream :
1/4 cup sugar
3 large egg yolks
1/8 cup flour
3 tbsp cornstarch (scant – err on the side of LESS)
1 1/4 cups milk
1 1/2 tsp vanilla
I like to make the cream EITHER before I make the cake OR while the cake is cooking – it just depends on your preference, for the cream will need to chill for awhile.
In a medium-sized bowl, combine the egg yolks and the white sugar. Whisk together until nicely ribboned. Ribboning is when the sugar and the eggs are combined so that the whisk, when lifted out of the pan, causes the mixture to run in a nice, thin ribbon of light yellow goodness back into the bowl.
Add the flour and the cornstarch and mix again until smooth and pasty. It should seem very thick and remain a light yellow. The flour and the cornstarch will act as thickening agents for the cream. When they are heated, they release amylose, a starch molecule, that expands when exposed to water. The eggs are also thickeners – as they cook, their protein structure changes to become less fluid and more solid.
Set aside for the moment.
In a medium saucepan, heat the milk until it is barely boiling. You will see steam rising from the milk and small bubbles forming on the sides of the pan. THIS NEXT STEP IS IMPORTANT SO PAY ATTENTION : We are going to do a little pouring and it might get messy but “if you’re alone in the kitchen, who’s to see ?” (Thank you Julia Child/Meryl Streep). Here is the game plan : because the eggs are not hot, but the milk IS hot, we don’t want to just dump the eggs into the milk as they will cook/curdle/the cream will not be creamy. It will be lumpy. No one wants tapioca-like cream when tapioca is not an ingredient. So, we have to temper the egg yolks – give them a chance to get used to the heat before throwing them into the fire..rather like when you don’t want to get into the cold ocean right away and you slowly tiptoe your way in.
Pour half of the hot milk into the egg mixture being sure to WHISK FRANTICALLY. Then, pour the eggy concoction into the OTHER half of the milk, do not stop whisking, and place THAT back on the heat. Whisk whisk whisk until you think your wrist is going to cry. The mixture should instantly start to thicken. Add vanilla. When it looks like custard, remove from heat and transfer to a clean bowl. Place this bowl IMMEDIATELY into the fridge or into an ice bath to stop the cooking. I never use the ice bath – I just chill mine – and all is usually well.
Let chill until cold and ready to use as filling !
Sponge cake :
5 large eggs
2/3 cup white sugar
1/2 tsp vanilla
1 1/4 cups flour
1 tsp baking powder
1/4 tsp salt
3 tbsp milk
2 tbsp butter
1/8 tsp cream of tartar (for egg whites)
Preheat oven to 350F. Line two 9” round pans with parchment paper (or grease well with butter). Sponge cakes can be a little tricky, so using parchment paper takes some of the anxiety out of the removal process. Separate three of the five eggs and allow them to come to room temperature before using.
In another bowl, blend together the flour, baking powder, and salt. I love nutmeg and I think it tastes really nice sprinkled into the cake batter, so I add a few shakes of that to the flour mixture.
Place the milk and the butter in a saucepan over low heat and remove one the butter has melted.
In a mixer (or by hand in a large bowl), beat 6 tablespoons of sugar with the yolks and the two eggs until they lighten significantly in color. Just as we did with the pastry cream, make sure they from a thin ribbon when lifted from the beater. Add the vanilla and mix well.
In another bowl, beat the three egg whites (with a pinch of salt and the cream of tartar) until they resemble soft peaks. If you are doing this by hand, it can be very tiring – soft peaks should allow the whisk to lift up, make a poof, and then that poof will stay stationary.
Add the flour mixture alternately with the warm milk mixture until just combined. Be careful not to overmix as the batter has yet to be folded.
HERE COMES THE BEST PART ! Fold the egg whites into the batter very gently. In a sponge cake, the egg whites are the rising agent – there is no baking powder that causes the cake to expand. Instead, it is the air trapped in between the newly-arranged proteins of the egg white that give the cake is sponginess/spring. That said, if you mix too much, it will fall and taste rubbery. Not enough ? You’ll have blips of egg white (that don’t taste like anything) interspersed throughout. It’s a delicate balance but aim for a swirled effect and the cake should turn out fine.
Pour into prepared pans and bake until golden brown and springy to the touch – about 20 minutes, depending on the strength of your oven.
Chocolate glaze :
6 ounces (or so) of nice dark chocolate, chopped (I use chips)
1/2 cup cream
1 1/2 tbsp butter
Optional : A little amaretto or frangelico adds a nice touch.
Place the cream and the butter in a pan over low heat. Once it begins to simmer, pour the chocolate in and let stand for 2 minutes (off the heat) before whisking smooth. Add the liquor if desired.
Assembly :
First, take one layer of the cake and dust the top with confectioner’s sugar – this will make it less sticky and easier to handle when placing it on the cake stand (or plate).
Remove the cream from the fridge and spread over the cake layer – don’t be afraid to load it up. Some might ooze out the sides, but that can be tidied up later. The cream is my favorite part, so I’m not really fussed if it’s a smidge messy.
Place the final cake layer on top of the cream and slowly spread the warm chocolate ganache over the layer. Do one thin layer, wait until it cools a little, then add another layer to avoid too much dripping. That said, I think part of a Boston Cream Pie is a few rivulets of chocolate down the sides…but it’s up to you.
COVER IN CANDLES, SING TO THE OLD MAN, AND ENJOY !
Bon appétit !
scratchbatch 