Doubanjiang (Sichuan Fermented Bean Paste — Aged vs Fresh)
Pixian county, Chengdu, Sichuan province, China. Documented production for over 300 years. Pixian doubanjiang holds a protected geographical indication in China. The paste is central to the development of modern Sichuan cuisine.
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.