Season the Classic Steakburgers with Worcestershire Sauce, salt and pepper. Cover and refrigerate until needed. Heat a sauce pan over medium high heat, add the butter. Once the butter is hot, sauté the onions, garlic and mushrooms. Deglaze the pan with red wine. Allow the wine to reduce to almost dry. Remove the pan from the heat and fold in blue cheese. Remove the seasoned Steakburgers from the refrigerator. Place 1-2 oz. of the stuffing in the middle of one of the patties. Place the second patty on top of the first patty and seal the edges. Place the burgers on a preheated grill. Cook the burgers to your desired doneness. During the last five minutes, baste with steak sauce. Place the cooked burgers on the toasted ciabatta bread and serve.