Irvine-based Ruby’s Diner Inc. has debuted a new small-format, quick-serve eatery at Westfield Plaza Bonita mall in National City.

The retro-diner operator, which has three full-service restaurants in San Diego County, said the new format, called Ruby’s Dinette, features a Mid-Century Modern décor evoking American diners of the 1950s, with a nod to futurist “Googie” architecture seen in Los Angeles in the 1960s.

The new restaurant is in the food court of the mall, located at 3030 Plaza Bonita. The retail center is among seven in San Diego County operated by Australia-based Westfield Group.

Ruby’s was started in 1982 and operates 37 restaurants in California and five other states, evoking 1940s and 1950s-style diners. The eateries serve comfort foods including burgers, salads, milkshakes and desserts.