Hearty Breakfast Casserole

My favorite breakfast casserole…

1 (20 ounce) package frozen hash browns, thawed
1/2 cup cheddar cheese
1/4 cup vegetable oil
1 1/2 tablespoons chopped parsley
3/4 cup monterey jack pepper cheese
3/4 cup swiss cheese
1 (12 ounce) package sausage, cooked and drained
1 (4 ounce) can sliced mushrooms, drained
1/2 cup milk
6 eggs, beaten
1 teaspoon garlic salt
1/4 teaspoon pepper
6 -8 slices tomatoes (thin slices)

Preheat oven to 450 degrees.
In a medium bowl, combine the potatoes, cheddar cheese and oil.
Mix well.
Press mixture into a 9X13 dish.
Bake for 30 minutes until golden brown; remove from oven.
Reduce heat to 350 degrees.
In a large bowl, combine 1 tbsp parsley with the remaining ingredients except the tomato slices; mix well.
Pour over potato crust.
Bake for 25 minutes or until the eggs are set.
Place the tomato slices over the casserole and top with remaining parsley.
Bake 5 to 7 minutes longer.