📝 About This Recipe
Tauco is a legendary Indonesian condiment born from the ancient tradition of fermenting yellow soybeans with brine and sun-drenched patience. This golden-brown paste delivers an incredible depth of salty, savory, and slightly funky umami that serves as the backbone for countless Southeast Asian stir-fries and stews. Making it from scratch transforms simple legumes into a complex flavor powerhouse that far surpasses any store-bought jar.
🥗 Ingredients
The Legume Base
- 500 grams Yellow Soybeans (dried, high quality, debris removed)
- 2 liters Water (for soaking and boiling)
- 3 tablespoons Rice Flour (to coat the beans for mold growth)
- 2 tablespoons Wheat Flour (all-purpose)
The Brine and Aromatics
- 150 grams Sea Salt (non-iodized is preferred for fermentation)
- 100 grams Palm Sugar (finely shaved; can substitute with dark brown sugar)
- 1 liter Filtered Water (for the brine solution)
- 3 cm Galangal (bruised and sliced)
- 4 pieces Indonesian Bay Leaves (Daun Salam) (dried or fresh)
- 2 stalks Lemongrass (white parts only, bruised)
- 2 cm Ginger (peeled and sliced)
👨🍳 Instructions
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1
Thoroughly rinse the yellow soybeans in cold water. Soak them in a large bowl with 1.5 liters of water for at least 12 hours or overnight until they have doubled in size.
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2
Drain the soaking water and transfer the beans to a large pot. Add fresh water and boil for 45-60 minutes until the beans are tender but not mushy; they should still hold their shape.
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3
Drain the cooked beans and spread them out on a clean bamboo tray or a large baking sheet lined with a kitchen towel. Let them air dry completely until the surface is no longer damp.
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4
In a small bowl, mix the rice flour and wheat flour. Dust this mixture evenly over the dried beans, tossing gently to ensure every bean is lightly coated. This provides the medium for beneficial molds.
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5
Cover the tray with a clean cloth or banana leaves. Place it in a dark, warm, and draft-free area for 3 to 4 days. You are looking for a fine white fuzzy mold (Rhizopus oligosporus) to develop; if it turns black or smells putrid, discard and start over.
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6
Once the beans are covered in white mold and have formed a slightly cake-like texture, break them apart gently with your hands.
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7
Prepare the brine by dissolving the sea salt in 1 liter of filtered water. Stir until completely clear.
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8
Place the molded beans into a sterilized glass or ceramic crock. Pour the brine over the beans until they are fully submerged.
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9
Add the bruised galangal, ginger, lemongrass, and daun salam to the jar. These aromatics will infuse the tauco during the secondary fermentation.
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10
Cover the jar with a piece of breathable muslin or cheesecloth secured with a rubber band. Place the jar in a sunny spot (traditionally outdoors) for 3 to 4 weeks. The sun's heat facilitates the enzymatic breakdown.
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11
After the sun-fermentation, pour the entire contents into a heavy-bottomed pot. Add the shaved palm sugar.
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12
Simmer the mixture over low heat for 20-30 minutes, stirring occasionally, until the liquid has thickened into a syrupy consistency and the color has deepened to a rich chocolate brown.
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13
Remove the large aromatics (lemongrass, galangal, leaves). Allow the Tauco to cool completely before transferring to sterilized glass jars.
💡 Chef's Tips
Always use non-iodized salt as iodine can inhibit the fermentation process. Ensure all equipment is sterilized with boiling water to prevent the growth of harmful bacteria. If you live in a cold climate, place the brine jar near a heater or inside an oven with only the pilot light on to mimic the tropical sun. The longer you sun-ferment the beans, the deeper and more complex the flavor profile will become. If you prefer a smoother texture, you can pulse a portion of the finished beans in a blender before the final simmering step.
🍽️ Serving Suggestions
Stir-fry 2 tablespoons of Tauco with morning glory (kangkung), garlic, and bird's eye chilies for a classic Indonesian side. Use as a savory base for 'Swikee' (frog legs) or 'Tahu Tauco' (braised tofu and shrimp). Mix with lime juice, sugar, and shallots to create a pungent dipping sauce for grilled fish. Add a spoonful to ginger-based beef stews to provide an instant hit of salt and earthiness. Pairs beautifully with a cold glass of jasmine tea to cleanse the palate from the salty fermentation.