Portillo is a popular fast-casual restaurant chain based in the United States, known for its Chicago-style food. Founded in 1963 by Dick Portillo, the restaurant originally started as a hot dog stand in Villa Park, Illinois. Today, it offers a diverse menu that includes items like Italian beef sandwiches, Chicago-style hot dogs, and chocolate cake shakes. The chain has expanded significantly, with locations primarily in the Midwest and California. Portillo's is recognized for its vibrant atmosphere and commitment to quality, making it a favorite among locals and visitors alike. The restaurant's unique blend of fast service and hearty meals contributes to its enduring popularity.