Heat the vegetable oil and sesame oil in a large wok or non-stick frying pan over high heat. Add the pork and cook for 2 minutes or until browned. Remove from the pan and keep warm. Add the black bean sauce, lemon juice and stock and cook for 1 minute or until the sauce has thickened slightly. Add the pork back to the pan with the bok choy and beans and cook for 1 minute. Sprinkle with cashews and serve with steamed rice or noodles. Serves 4.
+ Black bean sauce is available in the Asian section of the supermarket.