Leg of Lamb Black and Tan

Name: Leg of Lamb Black and Tan
Ingredients: 1 6 1/4-pound leg of lamb, boned, butterflied, trimmed of excess fat and sinew (reserve bone and trimmings for sauce); 1 small onion, chopped; 3 /4 cup chopped peeled carrots; 1 1/2 cups beef broth; 1 /2 cup Guinness Extra Stout; 1 /2 cup Harp lager beer; 2 tablespoons honey mustard; Disposable 11 3/4x8 1/2x1 1/4-inch aluminum baking pan; 1 /3 cup balsamic vinegar; 1 tablespoon granulated garlic; 3 tablespoons lemon pepper seasoning; 2 tablespoons (1/4 stick) chilled butter, cut into 4 cubes; 1 teaspoon (or more) honey