Heat a large pot of salted water over high heat. When boiling, add the pasta and cook until al dente. Keep aside 1 cup of the pasta water.
In a pan, add butter. Add garlic and cook for about 1 minute.
Mix in prawns and cook for a further 2 minutes.
Season with chili flakes, oyster sauce, dark soy sauce and light soy sauce.
Add the spaghetti and 2/3 cup of the pasta water.
Cook, stirring, for 3-4 minutes or until the liquid has been absorbed by the pasta and everything is looking super glossy and thick.
Add parmesan cheese and top with the spring onion. Mix well. Give this a taste and season with salt if needed.
Sprinkle with more spring onion and extra cheese, just before serving.