Thousand Oaks, California-based Baja Fresh Mexican Grill said it plans to open at least 16 new restaurants in the Chicago area over the next five years, through a partnership with Chicago-based Lettuce Entertain You Enterprises, which will develop and operate the restaurants. The Mexican quick-casual dining chain said it has signed an area-development agreement with Richard Melman, Lettuce Entertain You's chairman and founder, and his partner, CEO Steve Ottmann. The restaurants, planned for Chicago and certain northern suburbs, will join five Baja Fresh Mexican Grill restaurants already open in the Chicago suburbs.