1.Make asian pesto. Blend or process ingredients until well combined.
2.Sprinkle beef with pepper. Lightly spray a heated grill plate (or grill or barbecue) with oil; cook beef for 4 minutes each side, or until cooked as desired. Cover; rest for 5 minutes.
3.Meanwhile, cook noodles in a large saucepan of boiling water for about 2 minutes. Add buk choy; cook a further 2 minutes or until buk choy and noodles are tender; drain.
4.Serve beef with noodles, buk choy and pesto.
You can use other asian greens such as choy sum, instead of the buk choy. The asian pesto can be made a day ahead; cover tightly with plastic wrap and store in the fridge.