1.Season plain flour with salt and pepper in small bowl. Toss beef rump steak in flour to coat; shake off excess.
2.Heat vegetable oil for deep-frying in wok; deep-fry beef, in batches, until browned lightly. Drain on absorbent paper.
3.Reheat 1 reserved tablespoon of the oil in wok; stir-fry red chillies until fragrant. Return beef to wok; stir-fry until hot.
4.Serve beef with lime wedges; sprinkle with fresh coriander leaves.