1You will need a med-large casserole dish and a heave duty skillet.
In the skillet fry bacon till crisp. Remove from skillet with a sloted spoon,drain and crumble,save..
In the bacon drippings add onion and mushrooms.Cook for 3-5 minutes. Remove with slotted spoon. Now I save my bacon drippings. But you can do what you will.
2In a mixing bowl add ham,bread cubes, cheese,onions,mushrooms,and bacon. Toss to mix well.Spread evenly in a med-large casserole dish.
3In a medium mixing bowl,beat together egg whites and half-half. Pour mixture over the bread mixture.
Using a fork press down on bread mix to help absorb the liquid. Top with parmesan cheese.cover with foil.
4Pre-heat oven to 375 degrees. Bake casserole covered for 25 minutes..Uncover and top with some chedder cheese. Bake uncovered for 10 to 15 minutes until puffed and golden brown...