Doubanjiang — the 'soul of Sichuan cuisine' — is a fermented paste of broad beans (fava beans) and chillies that is to Sichuan cooking what soy sauce is to Japanese: the fundamental savoury, spicy foundation that appears in an enormous proportion of the region's dishes. The finest version, Pixian doubanjiang from Pixian county in Sichuan province, is aged for one to three years in clay pots under the open sky, turning and aerating regularly, until it achieves a complexity of fermentation and umami that younger versions cannot approach.
The paste is made by layering fermented broad beans (pre-inoculated with Aspergillus moulds for the initial fermentation) with fresh chillies, salt, and sometimes wheat flour, then allowing a long secondary fermentation and aging. The colour deepens from bright red to a dark, brick-reddish-brown with age; the flavour becomes more rounded, less harsh, and more deeply umami. Fresh (young) doubanjiang has a pungent, sharp character; aged has depth, complexity, and a mellow savouriness.
The critical technique in Sichuan cooking is frying doubanjiang in hot oil — called 'stir-frying the red oil' — at the beginning of a dish. This step, done correctly, transforms the paste: the chilli pigments dissolve into the oil creating the characteristic Sichuan red oil; the raw, astringent edges are cooked out; and the fermented bean flavour deepens. Underfrying produces a raw, harsh result; overfrying burns the chilli and produces bitterness. Two to three minutes over medium-high heat until fragrant and the oil turns red is the target.
Doubanjiang is the foundation of mapo tofu, doubanjiang-braised fish (douban fish), dan dan noodles, and countless Sichuan stir-fries and braises.
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The Method
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Soak broad beans overnight in cool water; drain and rinse thoroughly.
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Steam beans for 45 minutes until completely tender; cool and crush lightly with a fork — do not pulverise.
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Toast flour in a dry pan over medium heat for 3 minutes, stirring constantly, until pale tan; cool.
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Combine crushed beans, toasted flour, salt, and water in a glass vessel; fold until cohesive — texture should resemble wet sand with distinct bean pieces.
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Toast Sichuan peppercorns briefly if using; crush and stir through paste.
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Cover with cheesecloth; ferment in cool, dark conditions (12–15°C ideal) for minimum 6 months, stirring weekly.
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At 6 months: young, fruity, peppery — use in mapo tofu, chilli oils. At 2+ years: deep, funky, complex — use sparingly as umami base.
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Transfer to sterilised jars; keep refrigerated or cool storage indefinitely.
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USE: 1–2 tbsp (20–40 g) per dish as foundation for Sichuan cuisine; blooms in hot oil before sauce construction.
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DOUBANJIANG (Sichuan Fermented Bean Paste)
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Yield: 750 ml jar | Fermentation: 6–36 months
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500 g dried fava beans (or yellow soybeans)
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20 g koji (Aspergillus oryzae) or koji powder
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150 ml filtered water (for initial hydration)
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Soak dried beans overnight in cold water; drain and cook in fresh water until completely tender (1.5–2 hours), then drain thoroughly.
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Inoculate cooled beans with koji powder; spread on clean cloth and ferment at 18–22°C (64–72°F) for 5–7 days until white mycelium develops.
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Transfer koji-colonized beans to sterilized glass jar; mix in sea salt (approximately 25–30% by weight of beans).
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Cover with muslin and ferment in sunlight at 15–20°C (59–68°F) for minimum 6 months; aged 2–3 years develops richer, more complex profile.
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Stir twice weekly during first month, then weekly; paste will gradually darken and intensify.
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Once fermentation is complete, transfer to airtight container and refrigerate.
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FRESH (6 months): fruity, slightly sweet, lighter colour. AGED (24+ months): deeper umami, denser texture, mahogany colour. Use 1–2 tbsp per dish.
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For mapo tofu: fry doubanjiang with garlic and ginger first, add stock, then tofu — this sequence extracts maximum flavour
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A teaspoon of doubanjiang added to any meat braise adds a savoury depth that is impossible to identify but impossible to miss
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For the characteristic Sichuan red oil, fry 3–4 tablespoons of aged doubanjiang in 100ml neutral oil until the oil is deeply red, then strain — this becomes a condiment in its own right
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Combined with black bean paste (douchi) for mapo tofu for additional fermented depth
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Keeps refrigerated for months — the fermentation continues slowly
