Steamed Stuffed Bitter Melon

• 4 water chestnuts (fresh)
• 2 bitter melons
• 2 scallion (minced)
• 1 egg
• 130 gr pork
• 38 ml shaoxing wine
• 30 ml peanut oil
• 26 gr fermented black beans
• 16 ml soy sauce (thin)
• 16 ml sesame oil