Heat the oil in a preheated wok. Put the meat in the wok and fry on all sides for approx. 2 minutes. Add garlic and onion rings and fry for about 2 minutes. Put the sweet potatoes, curry paste and coconut milk in the wok and bring to the boil. Then reduce the heat, put the lid on and let everything simmer for about 15 minutes (until the potatoes are done). Serve hot. Serve with the cooked rice.