Heat vegetable oil in a large skillet over medium heat.
Add minced garlic and sauté until fragrant, about 1 minute.
Add shredded cabbage, carrots, bean sprouts, bell peppers, and mushrooms to the skillet.
Stir-fry the vegetables until they are tender-crisp, about 3-5 minutes.
Season the vegetables with soy sauce, sesame oil, salt, and pepper. Stir well to combine.
Remove the skillet from the heat and let the filling cool slightly.