Green Day, Metallica bassists jam on chaotic BottleRock culinary stage

From left: Chef Jose Andres, Green DayÕs Mike Dirnt and MetallicaÕs Robert Trujillo during a culinary demonstration at BottleRock on Saturday, May 27, 2017, in Napa, Calif. From left: Chef Jose Andres, Green DayÕs Mike Dirnt and MetallicaÕs Robert Trujillo during a culinary demonstration at BottleRock on Saturday, May 27, 2017, in Napa, Calif. Photo: Santiago Mejia, The Chronicle Buy photo Photo: Santiago Mejia, The Chronicle Image 1 of / 75 Caption Close Green Day, Metallica bassists jam on chaotic BottleRock culinary stage 1 / 75 Back to Gallery

Liam Mayclem did his best to keep order.

But there was only so much the emcee of the BottleRock Napa festival’s Williams-Sonoma Culinary Stage could do when chef Jose Andres was joined by a trio of superstar bass players — Green Day’s Mike Dirnt, Metallica’s Robert Trujillo and Dave Matthews Band’s Stefan Lessard (plus Guns N’ Roses and Velvet Revolver drummer Matt Sorum) —for a chaotic cooking demonstration on Saturday afternoon.

Wielding a whole bone-in Jamon Iberico ham and wearing a T-shirt that read “I Am An Immigrant,” the star Spanish-American chef Andres took the stage and immediately poured a round of cocktails for his temporary line cooks.

“Do we love this festival or what?” Andres bellowed.

The musical supergroup, playing on bass guitars built out of pizza peels, kicked into an improvised jam that quickly evolved into what sounded like the “Seinfeld” theme song.

As for the food, the recipe involved dumping a bag of Andres’ signature potato chips into a bowl of eggs. They may have mentioned what they were making at some point, but it didn’t matter.

It was all about the spectacle.

“If we don’t make it, we call it scrambled eggs,” Andres said, sensing the cooking demonstration was going slightly amiss.

Dirnt made himself useful by grating generous portions of black truffle over mounds of cheese and bread, making some very expensive sandwiches that the entire crew somehow neglected on the grill long enough to burn.

There was only one way to finish off the demo.

“Do you guys want more bass?” Mayclem asked the bewildered crowd, leading to another boisterous jam session of less than platinum-selling quality.

To close the whole thing out, Trujillo’s 12-year-old son — who not only plays in Sunday openers the Helmets, but is also a member of the reconstituted lineup of Korn — took the stage for a pizza peel bass solo with one of the charred sandwiches stuffed in his mouth.

Aidin Vaziri is The San Francisco Chronicle’s pop music critic. E-mail: avaziri@sfchronicle.com Twitter: @MusicSF

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