Pork Meatballs with Carolina Gold Sauce

Name: Pork Meatballs with Carolina Gold Sauce
Ingredients: 1 large egg, lightly beaten; 1/3 cup panko; 1/2 teaspoon kosher salt; 1/2 cup plus 1 tablespoon yellow mustard, divided; 1 tablespoon Worcestershire sauce, divided; 1 teaspoon chili powder, divided; 3/4 teaspoon garlic powder, divided; 3/4 teaspoon onion powder, divided; 1/2 teaspoon black pepper, divided, plus more for garnish; 1 pound ground pork; 2 tablespoons neutral cooking oil (such as canola); 1/2 cup chicken broth; 1/4 cup packed light brown sugar; 2 tablespoons apple cider vinegar; 1 tablespoon ketchup; 1 teaspoon hot sauce; Cooked polenta, for serving; Chopped fresh parsley, for garnish