Cook the spaghetti noodles first: Bring a pot of water to a boil, add a pinch of salt and a little oil to prevent sticking. Boil the noodles for about 5–8 minutes until al dente. Drain, rinse under cold water to stop the cooking, then drain again and toss with a little oil to keep from sticking.

Heat the rice bran oil in a large skillet or wok over medium-high heat. Add the minced garlic and chopped chilies, and stir-fry until fragrant.

Add the sliced sausage and fish balls. Stir-fry until everything is cooked through.

Add the cooked spaghetti noodles. Season with oyster sauce, fish sauce or soy sauce, and sugar. Stir-fry until the seasonings are well combined. Add the julienned fingerroot, torn kaffir lime leaves, Thai basil leaves, and fresh green peppercorns. Stir-fry until the herbs are fragrant, then transfer to a serving plate.