Egg and Hash Brown Casserole

INGREDIENTS

• 1 (20 ounce) package frozen O'Brien hashbrown potatoes, thawed
• 1/3 cup vegetable oil
• 1 (12 ounce) package bulk pork breakfast sausage
• 6 eggs, beaten
• 1 cup sliced fresh mushrooms
• 3/4 cup shredded pepperjack cheese
• 3/4 cup shredded Swiss cheese
• 1/2 cup milk
• 1 tablespoon chopped fresh parsley
• 1 teaspoon garlic salt
• 1/4 teaspoon ground black pepper
• 4 thin slices tomato
• 1 1/2 teaspoons chopped fresh parsley