Slice tofu noodles, king oyster mushrooms, onion, and green onion thinly.
Mix gochujang, soy sauce, oligosaccharide syrup, minced garlic, and sesame oil to make the sauce.
Heat cooking oil in a pan and stir-fry the green onion to make green onion oil.
Add king oyster mushrooms and onion, stir-fry, then add tofu noodles and continue stir-frying.
Add the sauce and mix well while stir-frying with the ingredients.
Sprinkle with sesame seeds to finish.