1.Cook rice in large saucepan of boiling water, uncovered, until just tender; drain. Cover to keep warm.
2.Meanwhile, heat oil in wok; stir-fry beef, in batches, until browned.
3.Reheat meat juices in wok; stir-fry onion and garlic until onion softens. Add ginger, chilli, capsicums, mushrooms, bamboo shoots and curry powder; stir-fry until vegetables are just tender.
4.Blend cornflour with stock in small jug; add to wok, stir to combine. Return beef to wok with peanut butter and sauce; bring to a boil, stirring, until sauce thickens slightly and beef is cooked as desired. Stir in peanuts.