Chow Down Chicago: Good Eats from the Windy City

Chicago-based fast food chain Portillo's is known for its Chicago-style hot dogs, Italian beef sandwiches, and, somewhat unexpectedly, its chocolate cake. While it's not exactly typical fast food fare, Portillo's chocolate cake has garnered a devoted following. But what makes the cake so popular? According to the book Iconic Chicago Dishes, Drinks and Desserts , Portillo’s uses a well-known brand of cake mix plus mayonnaise. Many copycat recipes for this cake posted on the internet also use these same ingredients, so the secret is out.  Portillo's got its start i n 1963 when Dick Portillo opened a fast food stand in Villa Park out of a small trailer he named "The Dog House." The trailer didn't have a bathroom and got its running water from a garden hose hooked up to a neighboring building. Today there are more than 70 Portillo’s locations across Chicagoland and the U.S., none of them in trailers. Portillo’s added chocolate cake to its menu during its earl