Step 1 Steps:
1. Marinade all the ingredients (except garlic and cooking oil) for an hour.
2. Heat wok, add cooking oil. Stir-fry garlic for 2 mins, add the marinade pork. Stir-fry the mixture until cook, or about 8 mins. Set aside to cool completely.
Step 2 Step:
1. In a bowl, mix ingredients for water dough (except butter), slowly add in water. Knead into a rough dough, add butter and knead to a smooth dough. Cover and set aside for 30 mins.
2. Mix ingredients for oil dough. Use butter knife to cut the butter and use fingertips to lightly rub the butter with flour until mixture look like fine breadcrumbs. Lightly press together the oil dough. Cover and keep in fridge for 30 mins.
3. Divide water and oil dough into 12 portions respectively.
4. Flatten the water dough, wrap the oil dough in it. Flatten with rolling pin, roll up. Cover and let it rest for 15 mins. Flatten from the long side, roll up. Cover and let it rest for 10 mins.
5. Use finger to pull up two end of the dough and press into middle. Flatten the dough into circle and stuff filling, egg wash and sprinkle with sesame seeds.
6. Bake at 210 C for 30 mins.