In a large bowl, pour in your self-raising flour. Gently add in your coconut yoghurt and begin stirring with chopsticks or a wooden spoon in a clockwise motion.
Once you begin to see a rough dough, begin kneading it in the bowl a few times.
Flour your surface and then knead your dough on there for 5 minutes until your dough is soft and bouncy. The dough should not stick to your hands, so if it does, then add more flour.
Cover your dough and set it aside while you make your filling.
In another bowl, combine your pork mince, lemongrass, garlic, scallions, light soy sauce, sesame oil, sugar, and gochugaru flakes. Stir until a smooth and moist paste forms.
Get your dough and slice it into 4 equal pieces.
Grab one piece of dough and flatten it out with your fingers into a circle that is around half an inch thick and around 3 inches in diameter.
Place a large spoonful of the filling into the centre of the wrapper and bring each side up and seal. Turn over the bao so the seal is facing downwards, and set it aside.
Repeat this step for all 4 bao.
Get your steamer and brush a layer of vegetable oil onto the base so that the bao doesn't stick. Place your bao into a steamer, add on the lid, and steam for 15 minutes on medium/low heat.
Once your steamed coconut buns are fluffy and cooked, remove them from the steamer and serve up with a sprinkling of spring onion and chilli oil.