HANALEI, HAWAII — Holey Grail Donuts, an operator of donut shops based in Hawaii, has raised a total of $9 million with its latest Series A funding round as it prepares to expand to the mainland.

The brand’s donuts are made with taro, a sustainable, starchy vegetable, and fried in organic, fair-trade coconut oil, highlighting Hawaii-grown ingredients including herbs, fruits and flowers. The concept, founded by brother-and-sister duo Nile and Hana Dreiling, began in a burger trailer in 2018 and has since grown to three shops in Hanalei and Honolulu, plus a food truck in Waikiki. This year, Holey Grail Donuts will open two locations in the Los Angeles area, as well as a food truck in Culver City, Calif.

Specialty donuts offered by Holey Grail include L&L, which has lemon zest-infused sugar, lime curd, finger lime caviar and begonia petals; Hail Mary, with cardamom and rose petals; North Shore, featuring Kauai-grown turmeric, tangelo and black pepper; and Lydgate Farms, with vanilla bean, single-origin cacao nibs and cherry. The team is building a California-centered supply chain to support its expansion, with local farmers to source produce, while maintaining its relationships with Hawaiian growers of taro, coconut oil and cacao.

The Series A round was co-led by Craig Shapiro at Collaborative Fund and Lee Fixel. The company’s seed round was led by Tony Conrad at True Ventures. Additional investors include Tony Hawk, James Freeman, Ligaya Tichy, Christopher Kostow, Hass Hassan, Stephan Jenkins, Yves Behar and Matt Mullenweg, among others.

“There’s a thrilling enthusiasm building around Holey Grail Donuts that reminds us of some of the other prolific food and beverage brands of our time,” said Mr. Conrad, who sits on the board for Holey Grail. “At the same time, Holey Grail Donuts is humbly unique in its approach to food and commitment to sustainable, plant-based ingredients while focusing intently on what customers care about most: taste. Nile and Hana are creating something really special.”