Slow Cooker Pork Belly (Samgyupsal)

Name: Slow Cooker Pork Belly (Samgyupsal)
Cuisine: Asian, Korean
Ingredients: 2 to 3 whole fresh pork belly (about 2 to 3-inch wide cut - 2.5 to 3 pounds); 1 medium onions; 1 tablespoon minced garlic; 1 tablespoon grated ginger; 2 teaspoons salt; 1 tablespoon doenjang (Korean fermented soybean paste, or use 1 more teaspoon salt); 1/4 teaspoon black pepper; Double this if you want to serve with a sauce; 2 tablespoons soy sauce; 2 tablespoons rice wine (or dry white wine); 4 tablespoons liquid from cooking the pork belly, (strained through a strainer.); 1 tablespoon sugar; Pachae (파채, (thinly sliced scallions) - 3 to 4 scallions); A handful of radish sprouts