A Boston cream pie is a cake that is filled with a custard or cream filling and frosted with chocolate. Although it is called a Boston cream pie, it is in fact a cake, and not a pie. Created by Armenian-French chef M. Sanzian at Boston's Parker House Hotel in 1856, this pudding and cake combination comprises two layers of sponge cake filled with vanilla flavored custard or crème pâtissière. The cake is topped with a chocolate glaze (such as ganache) and sometimes powdered sugar or a cherry.
The Boston cream pie is the official dessert of Massachusetts, declared as such in 1996. However, it is not mass-produced in Boston.
A Boston cream doughnut is a name for a Berliner filled with vanilla custard or crème pâtissière and topped with icing made from chocolate. 
- Forbes, Esther, and Arthur Griffin. The Boston Book. Houghton Mifflin Company: 1947.
- Morrisey, Louise Lane, and Marion Lane Sweeney. An Odd Volume of Cookery. Houghton Mifflin Company: 1949.
- History of Boston Cream Pie