Heat oil in a frying pan over high heat. Fry the pork belly until both sides turn golden.
Add ginger, spices, sugar, dark & light soy sauce. Pour in boiling water (just enough to cover the meat).
Turn the heat down low. Leave to simmer for about 1 hour until the meat becomes very tender.
Prepare the dough
IF KNEADING BY HAND: Mix flour, yeast, baking powder and sugar. Add water gradually. Mix with chopsticks/spatula until no more loose flour can be seen. Combine and knead briefly into a dough. Leave to rest for 10 minutes (covered). Knead again until very smooth.
IF KNEADING WITH A STAND MIXER: Mix flour, yeast, baking powder and sugar in the bowl. Knead on low speed until a very smooth dough forms (about 8 minutes)
Shape the buns
Divide the dough into 8 pieces. Roll each piece into a ball.
Press the ball with the palm of your hand. Flatten it with a rolling pin into an oval shape.
Fold the dough lengthways and place a piece of parchment paper in between (please refer to the tutorial video below).
Rest the buns
Place the buns in the steamer basket (line with steamer parchment paper or brush a thin layer of oil to avoid sticking). Make sure to leave ample space in between each one.
Leave to rest for around 30 minutes. Well-rested buns should be slightly bigger but not double the size (see note 6).
Steam the buns
Place the steaming basket onto a pot/wok filled with cold water. Start cooking over high heat.
Turn down to medium-low once the water is at a full boil. Count 10 mins from this moment.
Assemble the dish
Open up one bun. Place in coriander, then a piece of pork belly, top with kimchi, crushed peanuts and fresh chillies.
Store and reheat
You may keep cooked buns in the fridge for up to 4 days or in the freezer for 2 months. Reheat in the steamer. It takes about 4 minutes for fridge-kept ones or 6 minutes for frozen ones (no need to defrost). It’s not recommended to freeze uncooked buns.
You may also braise the pork belly in advance. Keep it along with the remaining liquid in the fridge for up to 4 days or in the freezer for 2 months. Reheat in a pan until piping hot.
Video
Notes
1. This recipe uses regular all-purpose flour (known as plain flour in the UK) which has a medium level of gluten (10-11g protein/100g flour). Please be aware that in some countries, all-purpose flour has a higher content of gluten. If that’s the case, replace 1/10 of the flour with corn starch then sift and mix.2. The flour-water ratio may vary depending on the brand of your flour. Adjust accordingly. The finished dough should be medium-firm and smooth.3. You may also use stir-fried Suan Cai/酸菜, Chinese pickled mustard greens, which is often found in classic Gua Bao. Other pickled vegetables, eg. German sauerkraut, works too.4. How to make toasted, crushed peanuts: Put skinless raw peanuts in a pan. Toast over low heat until slightly brown. Leave to cool then coarsely crush in a grinder or a mortar. Alternatively, you can put them into a resealable bag then crush with a rolling pin.5. You may also use ground peanuts instead which are popular in traditional Gua Bao (it’s usually mixed with a little sugar). Please feel free to use other nuts if you prefer, such as cashew nuts, walnuts, etc.6. The resting time required varies depending on the room temperature. It takes me 30 minutes in a room at about 25°C/77°F. So if it’s cooler in yours, extend the time a little and vice versa.