Chinese bbq pork bun (salapao sai mou daeng)

Ingredients

• 1.5 cups fermented dough
• 1.5 cups all purpose flour
• ½ cup cake flour
• ½ cup castor sugar
• 1 tsp ammonia
• 1.5 tbsp baking powder
• 2 cups all purpose flour
• ½ cup cake flour
• 1 tsp fermented glutinous rice flour
• ¾ cup water
• 2 tsp vegetable oil
• 2 cups Chinese B.B.Q. pork
• 1 cup B.B.Q. gravy
• 2 tsp wheat flour
• 2 tbsp light soy sauce
• 1 tbsp sugar
• 1 tsp sesame oil
• 2 tbsp vegetable oil