Cut sundae (Korean blood sausage) and vegetables into bite-sized pieces.
Heat cooking oil in a pan and stir-fry onion, green onion, and garlic.
Add sundae, glass noodles, and mushrooms, then stir-fry together.
Season with salt, pepper, and sesame oil.
Add Cheongyang chili peppers and chives, then stir-fry once more.
Transfer the finished White Sundae Stir-Fry to a plate.