Portillo’s, the fast casual chain known for hot dogs, Italian beef sandwiches and chocolate cake shakes, plans to go public, the company said Monday. Oak Brook-based Portillo’s confidentially submitted a draft registration statement with federal regulators. The company said it is still determining the number of shares it will offer and the price range it will seek, but the Wall Street Journal reported it is targeting a valuation of $2.5 billion to $3 billion.

The company declined to comment. Founder Dick Portillo started the business in 1963, selling hot dogs from a trailer in a parking lot in Villa Park. Today it has more than 60 restaurants, up from 40 in 2015, one year after Portillo sold the chain to private equity firm Berkshire Partners.