Use 9x13 greased pyrex dish. Place bread cubes and then cheese. Cook sausage slowly without lid. Drain, cut links into bite size pieces and place on top of cheese. Beat eggs, mustard, & milk. Pour over cheese. Refrigerate covered overnight. Dilute soup with evaporated milk. Pour over casserole. Bake at 300 degrees uncovered for 1 1/2 hours.