Reader Paul writes:
OK so here I am with three pastry school interns making Boston Cream Pies. One of them asks, “If this is a two-layer sponge cake filled with pastry cream and topped with a chocolate glaze, why is it called a pie?” My answer: “Durned if I know, but I’ll ask Joe”. So I’m asking.
Hey Paul! That’s a funny question. All I can say is that it’s one of those conundrums that probably has no real answer. There’s no question that in reality Boston cream pie is a cake, a pudding cake to be precise: two layers of sponge enclosing a whipped cream center. Legend has it that Boston cream pie was “invented” by a French pastry chef named Sanzian, an employee of Boston’s famous Parker House Hotel, in 1855. As the story goes he was looking for a way to dress up a business-as-usual English-style cream cake, a confection that had been around in America for about 100 years by that time. His solution was a chocolate glaze, something that would have been trendy then, since melt-able bar chocolate was relatively new. He dubbed it “Boston cream pie.”
Why? No one really knows, save to say that the terms “cake” and “pie” were a bit more, shall we say, flexible then. “Washington pie” was a dessert of that period, and it likewise consisted of two layers of spongecake around a sweet center, in that case some sort of fruit filling. To me it seems entirely possible that for some Americans a “pie” was any sort of filling enclosed between baked “crusts”, be they short or sponge. That’s just speculation of course. Hope this helped!