Cook the fettuccini in a large saucepan of salted, boiling water until al dente.

Meanwhile, heat a large frying pan over medium heat and spray with cooking spray. Add onion and garlic and cook, stirring often, for four minutes or until soft. Add mushrooms and cook for four minutes or until they are tender.

Drain fettuccini and return to saucepan. Whisk eggs in a jug with a fork. Add eggs, mushroom mixture, Parmesan, parsley, salt, and pepper to fettuccini and toss until well combined. Place saucepan over medium heat and toss for one minute or until egg mixture has just set. Serve immediately.