Cook the pasta according to package directions. Drain and set aside.
Heat a wok or large sauté pan over medium heat. When hot, add the butter, garlic and green onion. Cook for 1 minute or until very fragrant, making sure to keep an eye on the heat so that the garlic does not burn. Add in the mushrooms and cook for 2 minutes.
Remove from heat, add in the miso, oyster sauce and stir.
Miso Master Organic Sweet White (Low-Sodium) Miso is our sweetest, most delicate miso. This Short-Term miso has its own unique position in the miso universe; it has the least amount of salt and soybeans. Less salt means lower sodium content than other misos, so salt-conscious consumers can partake of the many health benefits of eating miso. Miso Master produces the only organic lower-sodium miso widely available in the natural food industry. Delicious is dressings, sauces, dips and mixed with Miso Master long term miso for soups!