Sausage souffle (casserole)

Crack eggs into a large bowl. Beat eggs until frothy. Add milk, dry mustard, and salt. Beat until well blended. Stir in bread cubes, then sausage and finally cheese. Spray a 9x13" pan with cooking spray. Pour egg mixture into pan, cover and place in the refrigerator overnight. Bake in a 350 degree oven for 45 minutes or until it is puffy and lightly browned. Let rest a few minutes before cutting into squares. This is good served with English muffins and fresh fruit. Note: I have also increased to 8 eggs to add volume to the casserole, but it is not part of the original recipe.