Mycological Society of San Francisco

Fungus Fair, December 7, 2025

The magical world of fermenting koji, an ancient fungi

Eleana Hsu

This class is taught by Eleana Hsu of Shared Cultures, a small batch producer in San Francisco specializing in koji. Inspired by traditional fermentation methods, wild foraged mushrooms, and the bounty of Northern California, Eleana Hsu and her partner Kevin Gondo are creating farm-to-jar misos, shoyus, and umami seasonings.

Their handcrafted small-batch approach has earned them a dedicated following, cherished by Michelin-starred chefs and home cooks. Each batch bursts with flavors you've never previosly experienced, making their products a culinary adventure like no other.

Workshop

The magical world of fermenting koji, an ancient fungi Join us for a hands-on and fully immersive 2 hour workshop, diving deep into the magical world of fermentation spotlight koji, an ancient fungi used to make miso, soy sauce, and sake.

This class will be broken down into two parts:

In the first half, we will first learn what koji is, how to make it, and its historical significance in food preservation. Discover through taste why this magical fungi graces the menus of some of the best restaurants in the world. All participants will be provided samples of different types of misos and ferments to taste during class to further their knowledge.
The second half of class is dedicated to a hands-on-workshop. We will all roll up our sleeves and ferment a miso made with koji, Rancho Gordo beans, and a seasonal mushroom.

Everyone will take home a 6 oz jar of the seasonal miso that will continue to ferment over time, and the knowledge to ferment something else on their own in the future.

Capacity: 30
Price: $45
Children may accompany an adult, but will need to have purchased a workshop ticket if they want their own jar of miso to take home.

Past Fairs

The Mycological Society of San Francisco has been hosting 1 or 2 Fungus Fairs each year since 1969. Fairs have been held in San Francisco County, Alameda County, San Mateo County, and Marin County. Historical information is available about previous Fungus Fairs: