Boil glass noodles in boiling water for 6 minutes, then rinse with cold water.
Julienne the beef, onion, carrot, shiitake mushrooms, and bell pepper.
Stir-fry the beef in a pan, then add the vegetables and stir-fry together.
Season with soy sauce, minced garlic, sesame oil, sugar, and pepper.
Add the boiled glass noodles and stir-fry quickly.
Place the japchae on top of the rice to finish.