fine green coleslaw, sour cream and guacamole, to serve
Preheat oven to 150°C. Season the chuck ribs generously, then sear in a heavy skillet over a high heat for 5 minutes, until well-browned. Rub with Mexican chilli powder, then arrange in a deep roasting pan with the stock, barbecue sauce and chillies. Cover with foil and bake for 3 hours, then uncover and bake for 30 minutes.
Pour the sauce into a medium saucepan, then boil rapidly for 10 minutes, until thickened. Ladle over the ribs, then bake for a further 15 minutes, until glossy. Grill the tortillas, then top with slaw, sour cream, guacamole and shredded beef.