Pork Buns (Nikuman)

Name: Pork Buns (Nikuman)
Prep time: 30 min
Cook time: 2 h
Total time: 2 h
Yield: 8 portions
Ingredients: 180 g water; 60 g milk; 20 g oil; 1 Tbsp sugar; 1 tsp dried instant yeast; 360 g plain flour; 2 fresh shiitake mushrooms; 2 spring onions; 80 g white cabbage leaf; 20 g fresh root ginger; 2 garlic cloves; 140 g pork mince; 40 g Japanese soy sauce; ½ tsp sugar; 15 g oyster sauce; 10 g sesame oil; 400 g water