Saucy Korean Fried Chicken Sandwich Recipe

Name: Saucy Korean Fried Chicken Sandwich Recipe
Ingredients: 2 (8-ounce) chicken breasts; 1 teaspoon ground black pepper; 1 tablespoon gochujang paste; 2 tablespoons soy sauce; ¼ cup sherry; 1 teaspoon minced garlic; ½ cup kimchi; ¼ cup mayonnaise; 2 teaspoons rice wine vinegar; 1 tablespoon honey; ½ teaspoon ground black pepper; 1 tablespoon sesame seeds; 1 cup cabbage slaw; 2 scallions, chopped; ½ cup cornstarch; 2 tablespoons baking powder; ½ teaspoon salt; Vegetable oil, for frying; 1 teaspoon sesame oil; 2 tablespoons gochujang paste; ⅓ cup brown sugar; 1 tablespoon soy sauce; 2 tablespoons minced garlic; 2 tablespoons ketchup; 4 brioche buns; 1 tablespoon unsalted butter