Chicken Wild Rice Casserole

I haven't tried this yet, but it looks awesome!

2- 4 1/2 oz cans, sliced mushrooms drained (reserve broth) or 16 oz sliced fresh mushrooms
1 cup (2 sticks) butter
small onion, chopped
1/2 cup all purpose flour
3 cups chicken broth
3 cups half-and-half
 4 boneless, skinless chicken breast halves cooked and diced
2- 6 oz boxes long-grain and wild rice mix, such as Uncle Ben's, cooked
1 cup slivered almonds, toasted and coarsely chopped
 4 Tablespoons chopped fresh parsley
 1 teaspoon salt
1/2 teaspoon pepper

Directions:
1.  Preheat oven to 350.  Grease a 9 x 13 x 2-inch casserole dish.
2.  If you use fresh mushrooms, saute them in a large skillet with 1 tablespoon of butter until tender, about 10 minutes.  Drain and reserve juice.
3.  In a large skillet, saute the onion in the remaining butter until tender.  Stir in the flour, cooking 2 to 3 minutes.
4.  Combine the mushroom juice with enough broth to make 3 cups of liquid.  Slowly stir the juice-broth mixture into the onion mixture.  Stir in the half and half.  Cook until the mixture is thickened.
5.  Add the sauteed or canned mushrooms, the chicken, rice, almonds, pimento, parsley, salt, and pepper.  Pour into prepare dish and bake for 30-45 minutes, or until most of liquid is absorbed.