Preparation

Koji is Aspergillus oryzae, a mold cultivated on rice or soybeans that's been central to East Asian fermentation for millennia. When you cure egg yolks in it, the koji's enzymes break down proteins into amino acids, creating intense umami while drawing out moisture to create a firm, almost cheese-like texture.

The addition of honey adds a subtle sweetness that plays beautifully against the funky, savory depth. These cured yolks can be grated over pasta, rice, salads, or eaten straight as a deeply satisfying snack.

Curing Instructions

1. In a medium bowl, mix the koji rice with honey and sea salt until evenly distributed.
2. Spread half of the koji mixture in a flat layer in a container with a lid (glass or ceramic works best).
3. Using your thumb, create 8 shallow indentations in the koji bed, spaced about 2 inches apart.
4. Carefully separate your eggs, placing one yolk in each indentation. Save the whites for another use.
5. Gently cover the yolks with the remaining koji mixture, ensuring they're completely buried but not crushed.
6. Cover the container and refrigerate for 5-7 days. The longer you cure, the firmer and more intense the flavor.
7. After curing, carefully uncover the yolks. They should be firm to the touch and a deep orange-gold color.
8. Wrap each yolk individually in cheesecloth and hang in the refrigerator for an additional 3-4 days to dry further. Place a plate underneath to catch any drips.
9. Unwrap and store the cured yolks in an airtight container in the refrigerator for up to 2 weeks.
10. Grate or slice thinly over dishes just before serving. A microplane works beautifully for creating delicate shavings.