Big, bold flavours and rustic cooking methods are the hallmarks of China’s far northwest, where the people are Turkic, not ethnically Chinese. They have more in common culturally and religiously (they’re mainly Muslim) with Central Asia, which Xinjiang borders. Cumin, chillies and sichuan peppercorns are common flavourings and vegetables such as tomatoes, eggplant and potatoes are widely eaten. In those parts, a dish like this would be accompanied by copious amounts of thick, chewy, wheat noodles. This recipe can easily be halved if you aren’t feeding a crowd.