W Brothers is a fermentation-focused restaurant founded by brothers Hiroshi and Toshiharu Watanabe. After honing their skills at culinary institutes and acclaimed restaurants, they opened W Brothers to showcase the remarkable power of koji, Japan’s revered national fungus.
Koji, created by cultivating Aspergillus oryzae on steamed grains like rice, barley, and soybeans, forms the foundation of traditional seasonings such as miso, soy sauce, mirin, and sake. At W Brothers, dishes and drinks are crafted using enzyme-rich, handmade rice koji, preserving the live enzymes through careful low-temperature fermentation without heat treatment.
