Heat sesame oil in a large pot over medium heat, add chopped onion, sliced mushrooms and the white parts of the green onions, (reserve green part for garnishing) and cook until mushrooms release thier liquid and onions are soft and translucent.
In a small bowl combine Soy sauce, vinegar, ginger, salt, pepper and chili sauce, set aside.
Add pork to the mushrooms and onions. Brown the meat, breaking up the meat as it cooks.
Add minced garlic and cook until fragrant, about 1 minute.
Add cabbage to the pot and pour in sauce, stir well to combine all the ingredients.
Cook until cabbage is soft, about 15-20 minutes and most of the liquid has evaporated and everything has cooked down.
Stir in bean sprouts, snow peas and red bellpepper strips; stir well to combine.
Cook an additional 1-2 minutes just to heat them but keep them crisp tender.
Serve topped with reserved green onions.
Top with a sprinkle of sesame seeds or wonton strips to serve