Place pork belly in a large pot with enough cold water to cover. Add 1 green onion and 4-5 Sichuan peppercorn seeds. Bring to boil and simmer for 30 minutes. If you are cooking a larger amount, cut the pork belly into sections around 15 cm long (keeping note 1) Transfer out and set aside to cool down.
Smash the head of garlic sprouts and then cut the head part and leaves into 1.5 inch sections. Remove the seeds of red pepper and cut into pieces too.
Heat up around 1 teaspoon of oil in wok (not too much, otherwise the dish might be over greasy), fry the pork belly for around 1-2 minutes (Note 2)until they begin to loose oil and slightly brown.
Move the pork slices out and leave oil only, fry ginger, garlic and scallion until aroma. Place doubanjiang and dou-chi, fry for another half minute. Return pork slices and give a big stir fry to combine well.
Add red pepper, fry for another half minutes. Lastly, place garlic spouts and light soy sauce. Combine well and transfer out immediately.
Serve with steamed rice.
You can boil a larger amount for example 600g once and keep the left half for another stir frying in following 2 days. Cool down completely and keep in refrigerator, covered with plastic wrapper.If the pork belly is fatty, fry for a longer time can reduce the oil it contained. However if the pork belly is with lots of lean meat, do not over-fry it. Otherwise, the slices will dry out.