Step 1

Place noodles in a large heatproof bowl. Cover with plenty of boiling water. Set aside for 3 minutes. Drain and separate.

Step 2

Heat wok over high heat. Once hot, add 1 tablespoon of the oil. Swirl the oil around the wok to coat the sides. Add half the beef and stir-fry for 1-2 minutes or until just cooked. Transfer to a plate. Repeat with the remaining beef.

Step 3

Reheat wok over high heat. Add capsicum and water chestnuts. Stir-fry for 1-2 minutes. Add bok choy and 1 tablespoon water. Cover and cook for 1 minute or until leaves start to wilt.

Step 4

Return beef to the wok with the noodles and black bean sauce. Toss for 1-2 minutes or until heated through and well combined. Remove from heat and toss in bean sprouts. Sprinkle with cashews and serve.