Turkey Cranberry Sliders

Name: Turkey Cranberry Sliders
Ingredients: ½ cup (1 stick) unsalted butter; 4 garlic cloves, finely chopped; 1 small onion, chopped; 1 lb. leftover roast turkey meat, torn or cut into bite-size pieces or 1 lb. sliced deli turkey; 6 oz. white American and/or provolone cheese, chopped; Kosher salt and freshly ground black pepper; ⅓ cup leftover cranberry sauce; 3 Tbsp. mayonnaise; 1 (12-oz.) package King’s Hawaiian rolls or 12 small soft dinner rolls, split in half and lightly toasted; Leftover mashed potatoes, reheated (optional); 2 pickled hot cherry peppers, seeded, chopped (optional)