French Onion Casserole - cooking recipe

Ingredients

3 medium onions
4 tablespoons butter
1 1/2 cups fresh mushrooms
2 cups shredded swiss cheese, divided
1 (10 3/4 ounce) can cream of mushroom soup, undiluted
5 tablespoons grated parmesan cheese (optional)
1 (5 ounce) can evaporated milk
2 teaspoons soy sauce
6 slices French bread (cubed)
1/4 cup chopped fresh parsley (optional)

Preparation

Sice the onions crosswise, cut each slice in half.
Melt the butter in a frypan, cook the onions and the mushrooms until tender.
Spoon the mixture into a lightly greased baking dish.
Sprinkle with 1 cup Swiss cheese.
In a bowl, combine the soup, evaporated milk Parmesan cheese (if using) and soy sauce; pour the mixture over the cheese.
Top with the bread cubes, and the remaining 1 cup Swiss cheese.
Sprinkle with parsley (if using).
Cover, and refrigerate for 4-8 hours.
Let stand at room temperature for 30 minutes before baking.
Bake, covered in a 350 degree oven for 30 minutes.
Uncover, bake for an additional 15-20 minutes.
Let stand for 5 minutes before serving.