Nicasio Valley Cheese Company’s head cheesemaker, Bryan Ackerly, broke up curds while making Loma Alta on Tuesday. The company’s Foggy Morning won a Best of Division award at this year’s state fair. David Briggs

Seana Doughty has a case of O.C.D.: “obsessive cheesemaker disorder.”

With a self-described “extreme nerdiness” in her scientific approach and a bit of creative flair, she operates Bleating Heart, a micro-creamery in Tomales that churns milk from 100 sheep and 10 cows on Marissa Thornton’s ranch into some of the world’s top cheeses.

Approaching their fifth anniversary, Bleating Heart’s cheeses won top honors at this year’s California State Fair: Fat Bottom Girl, a semi-hard, sheep’s milk cheese whose accidental rotund shape inspired its name, and Moolicious Blue, a semi-soft cheese available from cow’s milk year round, took home the two Best of Show awards. Funky Bleats, drawing from their sheep’s milk and excess goat’s milk from a nearby ranch, also won the Best of Division award for a California original.

After multiple denials from banks, Bleating Heart recently received a loan from Whole Foods to expand its facilities in hopes of tripling its production. “I think the North Bay rivals some of the most famous cheesemaking regions. Personally, I may be biased since I’m here,” Ms. Doughty said, laughing, “but I do think we have a reputation for being world-class cheesemakers. We have cow dairies, we have sheep dairies, we have goat dairies and we even have water buffalo dairies. No place else can say that.”

The area’s reputation has developed quickly, less than two decades after Peggy Smith and Sue Conley started Cowgirl Creamery in the mid-1990s and Bob Giacomini convinced his four daughters to return home and make a rich, blue cheese for Point Reyes Farmstead Cheese Company in 2001.

West Marin dairies creamed the competition in the rest of the state awards. Nicasio Valley Cheese Company’s Foggy Morning, a cheese as light and creamy as its name, taken from cows milked in the morning at the Lafranchi Ranch, won another Best of Division award, along with golds for Nicasio Reserve, Nicasio Square and San Geronimo. Marin French Cheese in Hicks Valley won 11 awards, including three golds for Petite Supreme, Scholss and Blackberry Quark. Cowgirl Creamery’s Wagon Wheel, Mt. Tam and Red Hawk all took home gold. Point Reyes Farmstead’s Toma won a gold for its semi-hard Toma, and Barinaga Ranch in Marshall won gold for its Basque-style sheep’s milk Baserri.