Cook the pasta according to packet directions. Drain well.
Meanwhile, heat butter and 1/2 the oil in a large frying pan over medium heat. Add mushrooms. Cook for 5 minutes or until golden and tender. Add garlic and lemon rind. Cook for a further 2 minutes.
Combine lemon juice, chives and remaining oil in a small bowl.
Add pasta to frying pan. Cook, tossing, for 1 minute or until heated through. Remove from heat. Add the chive mixture and rocket. Season with salt and pepper. Toss to combine. Top with cheese and sprinkle with extra chives. Serve.