Shake Shack's Chocolate & Vanilla Vs. Black & White Shakes

The first Shake Shack location began as a hot dog cart in New York City's Madison Square Park in 2001, reports Investopedia. Founder Danny Meyer saw success with customers of the cart, and expanded into a more permanent kiosk just three years later. The kiosk sold hamburgers, hot dogs, milkshakes, and crinkle-cut fries to visitors.

The kiosk became so popular, in fact, that it wasn't uncommon to see lines around the entire park, with customers waiting up to three hours to get food. A "Shack Cam" was even installed so customers could check the line length before making the trek over to the park.

Though Meyer never intended to open an entire restaurant chain, Meyer didn't want his customers to miss out on enjoying his food due to long wait times. He expanded and opened a few more New York-area locations in 2010, and eventually, the popularity spread. Today, there are over 400 Shake Shack locations worldwide, according to the Shake Shack website.

At first glance, the Shake Shack menu might appear to have a duplicate item. The fast-food chain offers a vanilla and chocolate shake, blending together two of its popular, standard shake flavors. But it also sells the Black & White shake, taking inspiration from the iconic black and white cookies of New York City, where the chain got its start, via Investopedia. These cookies feature an even split of chocolate and vanilla icing. So, what's the difference between the two shakes?

According to Insider, the vanilla and chocolate shake blends together the two custards into one shake. Though the two flavors are beloved on their own, the site states that the mix is made even better by perfectly blending the two. The Black & White shake uses fudge sauce, rather than chocolate custard, to achieve the flavor blend. Unfortunately, the addition of fudge sauce too closely resembles the plain chocolate shake flavor, and the two tasted nearly identical when compared side-by-side.

Despite the similarity, Insider reports that both the chocolate shake and the Black and White shake tasted equally good.

The custard used to create Shake Shack's shakes is actually made in-house at each location daily by custard machines, as per the Shake Shack website. It uses milk, cream, egg yolks, and sweetener to create a perfectly creamy, slightly dense, frozen treat.

Founder Danny Meyer reportedly fell in love with custard after growing up in the Midwest, where the treat was invented. Meyer discovered that custard was not as popular outside of the Midwest, so his goal was to introduce it to the rest of the country through his own menu.

Once the custard is ready to serve, customers can order it in one of Shake Shack's hand-spun shakes, or by the scoop for the classic chocolate and vanilla flavors, via Shake Shack's menu. The fast-food chain even occasionally offers limited-edition custard flavors — and even served up a new flavor for every day of the week at one point. Previous releases included raspberry swirl, prune Armagnac, and blueberry lemon ricotta.