Bring a pot of water to a boil. Cook the spaghetti until al dente. Drain and set aside.
Heat a skillet over medium-high heat and add the melted butter. Cook until the butter starts to foam and turn slightly brown. Add the garlic and stir a few times before adding the noodles and oyster sauce. Stir to mix well.
Add the Parmesan cheese and stir to combine well with the noodles. Turn off the heat and serve immediately.