In a small bowl, add hoisin sauce, soy sauce, sesame oil, sugar, mirin, black pepper, and water. Mix well and set aside.
Fill a large bowl with hot water and add dried rice noodles to it. Let them sit according to the package instructions. Drain, run cold water over them and a tablespoon of oil. Set aside.
Place a wok over medium heat and add oil.
Once the oil heats up, onion and cook for a minute.
Add minced garlic and cook for 30 seconds.
Add chicken and cook for a minute or until it turns white.
Add slices of carrots and bell pepper. Cook for 2 minutes.
Add drained rice noodles, and pour sauce.
Stir well until everything combines well.
Garnish with freshly chopped green onions and serve.