Doubanjiang is the deep red-brown fermented paste at the heart of Sichuan cooking — a thick, coarse, oily mash of broad (fava) beans and red chillies cured with salt, plus some wheat flour and often a little soybean. Savoury, salty and intensely umami with a building chilli heat and a funky aged depth, the best is matured for years (chenniang Pixian doubanjiang) and fried in hot oil to bloom its colour and aroma as the base of mapo tofu, twice-cooked pork and countless braises.