Pixian doubanjiang

Step 1: Soak the 1 ⅛ lb dried split broad beans in boiling water for 2 minutes, then drain. Steam over a high heat for 10–15 minutes, until just tender but not mushy. Spread on a tray to cool to about 95°F.

Step 2: Toss the beans with 3 ½ oz plain wheat flour until every bean is coated, then sprinkle over oz koji spores (Aspergillus oryzae) and mix again.

Step 3: Spread 2 cm deep on a cloth-lined tray, cover loosely with a cloth, and keep at 28–90°F (an oven with only the light on) for 5–7 days, until the beans are covered with a yellow-green, sweet-smelling mould. Discard if you see black, pink or bright orange mould or smell rot.

Step 4: Meanwhile wash the 3 ⅓ lb fresh long red chillies and dry them completely for several hours. Pull off the stalks and chop them on a board into 5 mm pieces, or pulse briefly in a food processor.

Step 5: Mix the chillies with 8 oz salt and pack into a sterilised jar (hot wash, then 10 minutes in a 250°F oven), pressing until juice covers them. Leave loosely covered in a cool place for the same 5–7 days, pressing down daily.

Step 6: Dissolve 1 ¾ oz salt in 1 ¼ cups cool boiled water. Break the moulded beans into a clean 3 litre wide glass jar or clay crock, pour over the brine and stir. Cover with a cloth and leave in a sunny window or warm place for 2–3 weeks, stirring once a day with a clean, dry spoon, until the beans soften and smell savoury.

Step 7: Stir the chilli mash into the beans. Cover the mouth with a cloth or loose lid and age for 2–3 months, sunning by day where possible and stirring every morning. The paste darkens from bright red to red-brown and smells winey and savoury; a little dark liquid on top is normal. Discard if fuzzy or coloured mould spreads or it smells putrid.

Step 8: It is ready when deep red-brown and rounded in taste. Spoon into clean jars and keep in the fridge for up to 1 year, always with a clean dry spoon.