Portillo’s has launched a new dessert based it one of its most popular — and most iconic — menu items, thanks to a new collaboration from a famous New York bakery.

Portillo’s and Milk Bar, the famed New York dessert shop soon coming to the West Loop, launched a limited edition “Chocolate Cake Cookie” Tuesday, according to a press release. The new treat features the flavors of the restaurants moist chocolate cake and fudge frosting, baked into a Milk Bar cookie.

The individually-wrapped cookie was available at Portillo’s restaurants, and in a six-count cookie tin at Milk Bar’s online store. The cookie will be available while supplies lasts, the release said.

This fall, Milk Bar will open its first Midwest location in Fulton Market.

The shop, which will operate in partnership with the Boka Restuarant Group, will be located at 200 N. Green Street, on the first floor of The Hoxton hotel in the city’s Fulton Market district. An exact opening date was not provided.

“Famous for VERY good reason, there is perhaps no greater restaurant dessert idol than Portillo’s Chocolate Cake- plump, rich, soft, understated yet an absolute home run,” Milk Bar Founder Christina Tosi said in a release.