Wash the pork shoulder thoroughly.
Place the pork shoulder and water in a pot.
Add onion, green onion, garlic, ginger, and whole peppercorns together.
Add soybean paste and cooking wine.
Once it boils, reduce to medium heat and simmer for 50 to 60 minutes.
Take out the pork shoulder, let it cool, and slice it thinly.
Serve with lettuce, ssamjang (Korean dipping sauce), garlic, and chili peppers.