Hash Brown Casserole

1 lb. bacon
2 onions, chopped (I use just a bit of diced dried onion for Andrew's sake)
1 C. fresh mushrooms, sliced
4 C. hash browns
4 eggs
1 1/2 C. milk
1 tsp salt
1/4 tsp garlic salt
1/2 tsp pepper
cheese, to taste

Preheat oven to 375 degrees.  Grease a 9x13 pan.  Cook bacon until crispy, drain.  Set aside.  In 1 Tbsp bacon fat, fry onions and mushrooms until tender.  Place potatoes in prepared dish.  Sprinkle with seasonings, top with onions, mushrooms, and crumbled bacon.  Beat eggs and milk and pour over.  Sprinkle with paprika, for presentation, and bake uncovered for 45 minutes.  Top with cheese, as desired.