- Make the ssam sauce: In a small bowl, whisk together all the ingredients, thinning the mixture with 1⁄4 cup water. The sauce will keep, refrigerated, for several weeks.
- Make the scallion sauce: In a small bowl, stir all the ingredients together. The sauce will keep, refrigerated, for about 1 week.
- Make the bo ssam: Pat pork shoulder dry and season it well all over with salt. Place a large skillet or dutch oven over medium-high heat and add oil. When oil begins to shimmer, add pork shoulder and sear it on all sides, starting with the fatty side, until nicely browned, about 5 minutes per side.
- Transfer pork to a slow cooker with fat cap facing up. Sprinkle with brown sugar and red pepper flakes, cover cooker with lid, and cook on low setting for 10 hours, until very tender; it can cook for up to 15 hours if you’d like.
- To serve, remove pork from cooker and set it aside to cool slightly. Place sauces, oysters, kimchi, lettuce leaves, and pickles in separate serving vessels. Pull or slice the pork (it will let you know which it prefers) and arrange it on a platter. Instruct your guests to use a lettuce leaf like a taco shell and fill it with some pork, kimchi, sauces, some pickles, and an oyster. And provide plenty of napkins.
*Gochujang and doenjang can be purchased from any Korean grocery store and most Asian markets.