📝 About This Recipe
Originating from the Kyushu region of Japan, Yuzu Kosho is a fermented condiment that delivers an electrifying explosion of citrus brightness and chili heat. This vibrant green paste balances the floral, aromatic zest of the rare Yuzu fruit with the sharp bite of Thai bird's eye chilies and the deep mineral quality of sea salt. It is a 'secret weapon' ingredient that transforms simple grilled meats, sashimis, and broths into gourmet experiences with just a tiny dollop.
🥗 Ingredients
The Citrus Base
- 12-15 pieces Fresh Yuzu Fruit (Firm, bright yellow or green skins with no soft spots)
- 2-3 tablespoons Yuzu Juice (Freshly squeezed from the zested fruit)
The Heat
- 150 grams Green Thai Bird's Eye Chilies (Stems removed; use green for traditional color)
- 2 pieces Green Serrano Peppers (To add body and a different grassy note)
The Preservation & Depth
- 10-12% of total weight Fine Sea Salt (High quality mineral salt is essential for fermentation)
- 1 teaspoon Rice Vinegar (Optional, to help stabilize the color)
- 1/2 teaspoon Kombu Powder (For an extra boost of natural MSG/umami)
👨🍳 Instructions
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1
Carefully wash the yuzu fruits in cold water and pat them completely dry with a lint-free towel. Any residual moisture can introduce bad bacteria during fermentation.
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2
Using a microplane or a fine Japanese grater, zest only the outer colored layer of the yuzu. Avoid the white pith at all costs, as it is intensely bitter and will ruin the condiment.
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3
Place a clean bowl on a kitchen scale and weigh the collected yuzu zest. Set this value aside.
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4
Prepare the chilies by cutting off the stems. For a traditional texture, slice them lengthwise and scrape out the seeds and white membranes. If you prefer extreme heat, leave the seeds in.
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5
Finely mince the cleaned chilies by hand or pulse them in a food processor until they reach a consistency similar to the zest. Do not over-process into a liquid puree.
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6
Add the minced chilies to the bowl with the zest and weigh the combined mixture. Calculate 10% of that total weight to determine the exact amount of sea salt needed.
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7
Add the calculated sea salt and the kombu powder to the citrus-chili mixture. The salt is the curing agent that prevents spoilage.
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8
Using a mortar and pestle (Suribachi), grind the mixture together for about 5-10 minutes. This bruising action releases the essential oils from the zest and marries the flavors.
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9
Stir in 2 tablespoons of the reserved yuzu juice and the rice vinegar. The mixture should be a thick, slightly moist paste.
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10
Transfer the paste into a sterilized glass jar. Press it down firmly with a clean spoon to remove any air pockets.
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11
Wipe the inner rim of the jar clean, seal tightly, and place in the refrigerator.
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12
Allow the Yuzu Kosho to ferment in the fridge for at least 7 days, though 14 days is ideal for the flavors to mellow and the 'sting' of the salt to soften.
💡 Chef's Tips
Always use a kitchen scale; the salt ratio (10-12%) is critical for safety and flavor. Wear gloves when handling Thai chilies to avoid painful skin or eye irritation. If you cannot find fresh Yuzu, a mix of 2 parts lemon zest and 1 part lime zest is a respectable substitute. Ensure all equipment is sterilized with boiling water before use to ensure a clean fermentation. Store the finished paste in the back of the fridge where it is coldest; it will keep for up to 6 months.
🍽️ Serving Suggestions
Whisk a teaspoon into a bowl of hot Miso soup or Tonkotsu Ramen for a bright lift. Spread a thin layer over grilled yellowtail (Hamachi) or seabass. Mix with olive oil and soy sauce to create a sophisticated vinaigrette for arugula salads. Serve as a condiment alongside Yakitori (grilled chicken skewers). Stir into a bowl of hot Udon noodles with a soft-poached egg.