📝 About This Recipe
Originating from the mountainous Shan and Lanna regions of Northern Thailand, Thua Nao is a rustic fermented treasure often referred to as 'Thai Miso.' These hand-pressed discs are packed with a deep, savory funk and nutty complexity that serves as the soul of local curries and dips. Making them is a beautiful ritual of patience, where humble soybeans are transformed by heat, fermentation, and the golden Thai sun into an indispensable umami powerhouse.
🥗 Ingredients
The Legumes
- 500 grams Organic Yellow Soybeans (dried, high quality)
- 2-3 liters Filtered Water (for soaking and boiling)
Fermentation Essentials
- 10-12 large pieces Dried Banana Leaves (cleaned and softened, or use bamboo leaves)
- 1 bundle Rice Straw or Fern Leaves (optional, to introduce natural wild microbes)
Seasoning (Optional/Modern Style)
- 1 tablespoon Sea Salt (fine grain)
- 5-8 pieces Dried Bird's Eye Chilies (pounded into flakes)
- 30 grams Garlic (pounded into a paste)
- 15 grams Ginger (finely grated)
👨🍳 Instructions
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1
Rinse the dried soybeans thoroughly in cold water until the water runs clear. Remove any debris or discolored beans.
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2
Place the beans in a large bowl and cover with at least 3 inches of water. Let them soak for 12-15 hours (overnight) until they have doubled in size.
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3
Drain the soaking water and transfer the beans to a large heavy-bottomed pot or pressure cooker. Add fresh water to cover the beans by 2 inches.
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4
Boil the beans over medium-low heat for 4 to 6 hours (or 1 hour in a pressure cooker). The beans are ready when they can be easily smashed between two fingers with zero resistance.
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5
Drain the cooked beans, reserving about 1/2 cup of the cooking liquid. Let the beans cool slightly, but they should still be very warm (around 40°C/104°F) for the fermentation to begin.
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6
Line a bamboo basket or a wooden crate with clean, softened banana leaves. If using rice straw for traditional microbes, place a layer at the bottom.
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7
Transfer the warm beans into the basket. Cover the top with more banana leaves and weigh it down slightly with a clean cloth or a light plate to retain heat.
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8
Place the basket in a warm, dark, and draft-free area. Let it ferment for 2 to 3 days. You will know it is ready when the beans develop a pungent, ammonia-like aroma and a sticky, white filamentous coating (similar to Natto).
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9
Transfer the fermented beans to a large mortar or food processor. If you prefer the seasoned version, add the salt, chili flakes, garlic, and ginger now.
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10
Pound or pulse the beans until they form a coarse, sticky paste. You want some texture to remain, not a completely smooth puree.
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11
Prepare a flat surface or a bamboo drying mat lined with plastic wrap or clean banana leaves. Scoop about 2 tablespoons of paste and flatten it into a thin disc, about 3-4 inches in diameter.
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12
Place the discs under direct sunlight for 2 to 3 days. Flip them every few hours to ensure even drying. They are finished when they are hard, brittle, and dark brown.
💡 Chef's Tips
Ensure all equipment is meticulously clean to prevent bad bacteria from taking over the fermentation. If the beans smell 'rotten' rather than 'pungent and yeasty,' discard them and start over. For the best flavor, toast the dried discs over an open flame or in a dry pan until fragrant before using them in recipes. In humid climates, you can use a food dehydrator set to 50°C (122°F) for 8-12 hours to dry the discs. Store the finished dried discs in an airtight container in a cool, dark place; they will keep for up to 6 months.
🍽️ Serving Suggestions
Crumble a toasted disc into 'Nam Prik Ong' (Northern Thai Pork and Tomato Dip) for an authentic depth of flavor. Use as a vegetarian substitute for shrimp paste in Northern Thai curries like 'Kaeng Khae'. Grill a disc until charred, crumble over steamed sticky rice, and drizzle with a little soy sauce and chili oil. Dissolve a piece of the disc into a hot vegetable broth to create a quick, probiotic-rich savory soup. Finely grind the dried discs into a powder to use as a 'salt' or seasoning rub for grilled meats.