Boston Cream Pie

The Boston cream pie is actually a cake, not a pie. The idea of it being a pie most likely stems from the easier availability of pie tins over cake pans during the time the dish originated. (It might also originate from the use of the custard cream filling which is usually associated with pies rather than cakes.)
Created by French chef M. Sanzian at Boston's Parker House Hotel, opened in 1855, this pudding/cake combination comprises two layers of sponge cake filled with vanilla custard or crème pâtissière. The cake is topped with a chocolate glaze (such as ganache) and sometimes confectioner's sugar or a maraschino cherry.
A Boston cream doughnut is a local name for a Berliner filled with vanilla custard or crème pâtissière and topped with chocolate icing.
The Boston cream pie has been designated the official state dessert of Massachusetts, while the Boston cream doughnut is the official state doughnut.