Finely mince the garlic.
Finely slice the lemongrass (see instructions) then chop.
Peel the ginger then chop.
Thinly slice the chili and scallion stalks.
Heat the cooking oil in a wok or frying pan.
Keeping the heat at medium-low, gently cook the garlic, lemongrass, ginger, scallions and chili until a bit softened and lightly browned, about eight minutes.
Add the cooked noodles.
Season with soy sauce, fish sauce and lime or lemon juice. Sprinkle in the sugar. Cook, tossing often, until blended and the noodles are heated through.
Divide the noodles between two bowls. Top with sliced chicken teriyaki. Sprinkle with torn Thai basil and cilantro, and peanut powder. Serve at once.