Review: Shake Shack's New Custard Sundaes Are Sweet, Silky, And Worth Trying

Shake Shack recently rolled out two sundaes in select markets to test receptiveness to the idea, and you probably have two questions: "Don't people always want a sundae?" and "Wait, no, surely Shake Shack has had sundaes forever now." You're right on the first part but wrong on the second. You're probably thinking of the countless Shake Shack flavors of shake have rolled out over the decades since they use the same custard base. Yes, it's technically ice cream, but not all ice cream is technically custard. It's a square versus rectangle type of thing — or bourbon and whiskey. So please, give a frigid welcome to the Strawberry Shortcake Sundae and Shack Attack Sundae.

We tried both ice cream inaugurates at Shake Shack's Innovation Kitchen in lower Manhattan but, unlike our recent outing to find the brand's Zero Acre sugarcane-oil French fries, you don't have to be in New York to taste these sundaes for yourself. Keep reading for the low-down on the high-calorie heaven that is Shake Shack's new custard-based sundaes.

Select markets around the country are getting a trial run of the Shack Attack Sundae, made with two scoops of chocolate custard, and the Strawberry Shortcake Sundae, made with vanilla. Both are selling for $6.89. Shake Shack sundaes use the same fresh custard that the restaurant chain makes every day for its titular shakes; because it's custard, the frozen base is richer and denser than a lot of ice creams out there. 

Shake Shack's executive chef and VP of culinary innovation, John Karangis, says the cooked eggs, sugar, cream, and vanilla are then frozen slowly to create its signature texture. You can watch him assemble the sumptuous sundaes on TikTok, just in case you can't get to a Shake Shack that's selling them and want to try making your own at home.

While the flavors are familiar to anyone who has slurped the Shack's shakes, expect to be pleasantly surprised by the silken texture of the original article as it exists before getting spun out into a drink.

Both sundaes are served with whipped cream and a cute, pipsqueak-sized waffle cone. Karangis says the team figured people would crack the cone into the sundae, but we found that taste testers are just as likely to build themselves a little ice cream cone as a side dish — all of which is fine with the innovation team. "We were tasked with doing what we do," he says, "Which is elevating classics in an approachable way."

The Strawberry Shortcake Sundae has 560 calories and 26 grams of fat, including 14 grams of saturated fat. Its 73 grams of carbohydrates is largely thanks to 58 grams of sugar. Also, 10 grams of protein await you in this custard, so thank the eggs and milk for their contribution to your good macros. It marries vanilla custard with strawberry sauce, rainbow, sprinkles, and a cherry atop a shortcake bedrock.

The Shack Attack Sundae comes in a little heftier on the nutrition table at 800 calories, thanks to 45 grams of fat, of which a little over half is saturated fat at 24 grams. This chunk of chocolate has 93 grams of carbohydrates, comprised of 70 grams of sugar. It's also slinging 13 grams of protein, which ain't bad at all for a dessert. Ingredients-wise, it's an all-chocolate assault that reconstructs the Shack Attack Shake with brownie spongecake (we didn't know that was a thing either!) under chocolate custard, fudge sauce, and a crispy brownie crunch.

While some limited-time offerings end up contained to a small area or a couple of test markets, Shake Shack's rolling this one out broader than most. New Yorkers can get a sundae on the Upper West Side or the West Village Shack where we tried it. Long Island and New Jersey residents can head to the Westbury Shack in Garden City or Melville. New Jersey has options at either end of the Transit lines in Princeton or Wayne.

Most of the West Coast availability happens in San Diego at the Westfield UTC, Mission Valley, Little Italy, and Del Mar Shacks. Or custard connoisseurs can fill the cavern in their stomachs with a sundae in nearby Carlsbad, too.

And finally, the Southwest can't be left wanting, since it's hot there even in October. Nevadans, go ahead and get yourself some ice cream in Summerlin, Las Vegas, or Henderson. In Utah, your locations are The School Yard Shack in Sandy or Fashion Place in Murray.

Everyone else, we won't say you're missing out since these sundaes are expected to be pretty popular. You just can expect to wait longer for the almost inevitable rollout. If they put the white truffle menu out nationally, can ice cream really expect to stay in its warm-up uniform?

An utterly chocolate sundae almost feels like cheating, so credit executive chef Karangis and the Shake Shack team for paying attention to what creates variation in the final product instead of simply piling on the endorphins. We love the crunch and crispiness here, awash in the almost gelatinously thick chocolate custard, which approaches buffalo mozzarella for creaminess but stays on the smooth and buttery side of the chew. The Shack Attack Sundae all but dares you not to bite it.

When you do, there's cacao nib and sea salt here that pop out when you least expect them. Normally, the salt would hit first and vanish as your mouth mashes up the ingredients but, for some reason, it comes in at the end and it's glorious. You'll get the sweet chocolate you're used to from the fudge and brownie, but the last one standing in this chocolate rumble is the deeper and darker cocoa flavor between the custard and the nibs.

The shortcake is meant to absorb the vanilla and strawberry flavors trickling down. "Your best bite could be your last bite," says executive chef Karangis. We found it's true that this absorption really rounds out the flavor in a way that hadn't happened without the cakiness. The cake creates new tastes by way of deconstruction, and we're here for it. It's almost like eating two similar but different sundaes if you don't get any shortcake on your spoon. The ice cream and sauce on their own tend to blend into a single delicious flavor. The baked good helps separate the various notes of tartness, mellow spice, and sweetness.

Karangis says that the same principle applies here as it does in the hamburgers' construction, deliberately intending to let the ingredients soak into a potato bun so that the burger becomes even more flavorful as you eat. We think the Strawberry Shortcake might be the better pairing to the classic ShackBurger.

The new sundaes at Shake Shack are absolutely worth buying, especially since the burger joint's Hot Menu is still available, and you're going to want some fatty, freezing dairy to cool down your tongue. Order these two limited-time offerings together, and enjoy a meal of fire and ice.

If you're wondering which sundae you should get, well, we recommend both. Make two visits, if needed. But, say that can't happen. If we could only have one, we're a little inclined to say the Strawberry Shortcake comes together with a more delightful array of flavors that are bright and melodious. It's all about the taste. While the shortcake provides some nice dry texture in a wet ride of fruitiness, its full function is, as Karangis promised, to springboard all those other flavors. The sprinkles will likely slide by you, but boy does it all come together well.

Meanwhile, the all-chocolate Shack Attack (the Batman to Strawberry's Superman) is an effective one-punch knockout with texture. It's chocolate all the way down, and to its credit, those chocolates provide different flavors, but you're ordering this one because you want the crunch and cake of the brownies and cacao nibs to contrast a very silken custard. We found contrasts all come from the chew rather than letting this melody melt on the tongue. In the end, it comes down to what kind of eater you are.