Place frozen vegetables in a buttered 13 x 9 inch (33 x 23cm) baking dish. Top with turkey and croutons. In a large bowl, beat eggs, chicken broth, roasted red pepper and mustard. Pour over croutons. Sprinkle with cheese. Cover and refrigerate for at least 8 hours or overnight. Remove from the refrigerator 30 minutes before baking. Uncover and bake at 350 F (180C) for 35-40 minutes or until knife inserted near the centre comes out clean. Let stand for 10 minutes before serving.