Bring a medium pot of water to boil for the noodles.
In a small bowl, combine soy sauce, oyster sauce, fish sauce, brown sugar and sesame oil. Set aside.
In a wok or large frying pan on low heat, melt butter, add oil and garlic. Let cook for 2-3 minutes, stir frequently and make sure it does not brown. Add chili, if using, during the last 30 seconds.
Meanwhile, blanch the noodles for a minute. Drop the noodles directly into the garlic mixture. It’s ok to include a little bit of the cooking liquid as the noodles don’t have to be totally drained. Add the sauce and toss. That bit of cooking liquid helps the sauce evenly coat the noodles. Turn off the heat.
Add parmesan cheese and continue to toss the pasta until the cheese has melted.
Drizzle with sesame oil and toss in half of the green onions.
Serve on a platter and garnish with remaining green onions.