Kitchen Mysteries is a weekly exploration of oddities surrounding cooking and food. They could be recipes that fail when they shouldn't, conflicting advice from different sources, or just plain weirdness. If it happens in a kitchen, and you're not sure why, send a tweet to The Food Geek to find out what's happening.
John Feminella asks via Twitter:
Background: Okay, in October I am going to be a judge in the Charlottesville Pie Fest, and a question came up about whether we could have cheesecake in the Pie Fest. Author of Mrs. Rowe's Little Book of Southern Pies Mollie Cox Bryan suggests that no, cheesecake was not a pie. I disagreed, respectfully, then a huuuuge argument broke out. Of course, it was Twitter, so each individual retort was 140 characters or less, but the scope was vast. This is my side of things, supplemented by ideas that I've read over the course of the argument.
Back in the day, and to a lesser extent even today, everything was a cake. Generically, any small block of solid substance is a cake. We have crabcakes (which is a meatloaf or squashed meatball), we have urinal cakes (which are not at all tasty), and we have yellowcake uranium, which I am pretty sure isn't tasty, but I've not been close enough to try it. For all I know, it could be delicious. It certainly looks delicious.
Cakes are everywhere. Just because something is a cake does not mean it isn't also something else. A cake of soap is still a bar of soap. The problem comes with pastry because cake means something specific, which is generally a baked good, primarily made of flour, sugar, fat, and eggs, leavened in the oven during the baking cycle. Nobody should argue that crab cakes should be allowed in a wedding cake competition, because they are clearly different things. The name only takes you so far.
There are a few of classes of pie. Most standard pies (as opposed to pocket pies) are round, not much more than a couple of inches tall, and wider at the top than at the bottom. More often than not, pies are 8-10" in diameter, though there are some mini-pies that are closer to 3-4" in diameter.
Pies, traditionally, have two types of crust: the pastry crust and the crumb crust. The pastry crust we've covered before, and is a combination of flour, water, and fat, combined properly using, and baked. The crumb crust is a pulverized cookie or cracker that's mixed with fat and baked just to set.
Inside a pie can be just about anything, but when I think of pie, two categories stand out: fruit and custard. Fruit pies are things like apple, blueberry… you know what a fruit pie is. A custard pie is milk or cream mixed with sugar and egg yolk and some additives, and usually baked. As I say, there are other variations (pecan, peanut butter, pudding, etc.), but fruit and custard are the heavy hitters.
Given all of the above, let's talk about cheesecakes. Generally cheesecakes are cylindrical, 4-6" tall or more, have a baked custard center, and a crumb crust. With a minor change in appearance, any pastry that is a crumb crust filled with custard and baked, in my mind, is a pie. The addition of cream cheese is no more a disqualifier than the addition of bourbon would be.
So, in short, a cheesecake is a pie. It can also be a cake, but it can't not be a pie.