CakeSpy

So, Old School Frozen Custard has opened in what is quickly becoming Seattle's Ice Cream District in Capitol Hill, what with the recent opening of several other arbiters of chilled treats including Molly Moon's Ice Cream and more recently Bluebird Ice Cream. However, you'd be a fool to mistake frozen custard for your everyday softserve. Why? Well, Old School's website does their best to educate, under the heading "What is Frozen Custard?". As they put it:

We know what you're thinking, but you're probably wrong. Frozen custard is not flan, crème brûlée, or something your grandma throws in a pie.

as the narrative goes on, the differences are mainly to be found in two places. First, ingredients: frozen custard not only contains a minimum of 10% butterfat (this is the delectable thing that makes premium ice creams coat your tongue with deliciousness), but it also has 1.4% egg yolk by weight. It's the yolk that separates frozen custard from regular ice cream by adding a "richer, fuller taste and an indescribably silky texture."

The second difference is preparation: "The volume of regular ice cream is almost doubled by the air whipped into it during production (called overrun)," --crystals formed during this time can lead to a coarse texture in softserve ice cream. With frozen custard, the mix is continuously fed into and frozen in a barrel, avoiding this extreme aeration and resulting in a denser, creamier finish with 70% less overrun than regular ice cream. It's also served slightly warmer than ice cream: "In contrast to regular ice cream which is served just above freezing, Old School's frozen custard is served 18-20 degrees warmer, which allows for maximum flavor and doesn't freeze your taste buds."