Prepare all vegetables by washing and cutting them into bite-sized pieces.

Blanch broccoli in salted boiling water, then rinse in cold water and set aside.

Heat sesame oil in a pan and sauté chili peppers and white parts of green onions until fragrant.

Add mushrooms to the pan and stir-fry for a few minutes.

Add onions and continue stir-frying until translucent.

Add beef slices and stir-fry until almost cooked.

Add bell peppers, paprika, and broccoli, then stir well.

Season with black pepper and oyster sauce, then add a small amount of water.

Add bok choy and stir until evenly mixed.

Adjust seasoning with salt and thicken the sauce with cornstarch slurry.