The recipe for a Rockabilly Roundup goes something like this: Take some hip cats and kittens and add some hot-rods, tattoos and a bit of attitude — wrap tightly with some happening rockabilly tunes.

That’s the way it went Saturday at Pioneer Park in Calistoga as dozens of hipsters came out to play during the city’s fifth annual Rockabilly Roundup concert.

The sounds of some of the hottest rockabilly acts in the valley and throughout the Bay Area were resonating from the park and drew people in from all walks of life. Santa Rosa resident Irene Ramirez, 31, dressed as a 1950s businesswoman as she listened to Santa Cruz’s Los High Tops belt out their set.

“I’ve been into rockabilly for 13 years,” she said. “It’s (about) the clothes, the style and the music. It comes from the heart. This is what the roots of rock ‘n’ roll are about.”

Ramirez listened as Los High Tops performed to about 100 people and mixed their set with cover tunes such as Richie Valen’s “Come on, Let’s Go” and original music. Julia Johnson, lead singer for the band MissFire and the Detonations, led the crowd in the group’s “Medium Rare,” which talks about the band’s love of barbecue.

“You can fry it up or roast it too, shake it, bake it, a barbecue, I like it medium rare!,” Johnson sang to the crowd.

“Medium rare!” some in the audience responded to the band.

“My lyrics come from my soul, baby,” said Johnson, who is an Automotive Technology instructor at Skyline College in San Bruno. “It’s happy music.”

Lakeport resident Jason Ingham brought his 1933 Chevrolet Sedan, dubbed “Green Onions,” to the concert to share with the crowd. Ingham acquired the vehicle four years ago in Middletown.

“It was parked under a tree,” he said.

Ingham approached the owner and purchased the vehicle, which he rebuilt into a sweet ride. He placed a .327 cubic-inch engine into the sedan and applied a lime-green paint job with green flames on the side to crank up the coolness factor.

“Some people think it’s a fishing lure,” said Ingham jokingly.

Ingham said he brought Green Onions to the concert because, “It’s all old-style stuff, and that’s mainly a lot of what the rockabilly stuff is.”

Produced by Napa Musicians Performance Guild and the Calistoga Chamber of Commerce, Calistoga’s Rockabilly Roundup is the only event of its kind in the valley, said Dalton Piercey, event organizer and executive director of Napa Musicians Performance Guild.

Five years ago, the first Rockabilly Roundup came together because Piercey wanted to bring music to the valley, he said.

“I really wanted to do something for the rockabilly scene in the North Bay,” Piercey said.

So Piercey invited a bunch of rockabilly bands to the area and held the first event at Calistoga Inn, he said. Several years later, and now working with Calistoga Chamber of Commerce, Piercey expanded the concert to Pioneer Park and acquired some big-name sponsors such as Budweiser, Lucky 13 Clothing and Twin Pine Casino.

On Saturday, several groups including MissFire and the Detonations, Los High Tops, Buckshot Boys, Revtones, Royal Deuces and the Bluenotecats graced the stage and entertained the crowd.