Macaroni and Chicken Casserole

1 1/4 cups uncooked elbow macaroni 
2 tablespoons butter 
1/4 cup finely chopped onion 
4 ounces mushrooms, sliced 
2 tablespoons chopped green bell pepper (about half of a small bell pepper) 
2 tablespoons chopped pimiento-stuffed olives 
4 ounces (1 cup) shredded sharp Cheddar cheese 
1 cup sour cream 
1 teaspoon seasoned salt 
1 teaspoon pepper 
1 1/2 cups diced cooked chicken 
1/4 cup milk 
1/2 cup soft bread crumbs, tossed with a few teaspoons melted butter - for topping chicken casserole


Cook and drain macaroni, following package directions; place in a large mixing bowl.


In a large skillet, melt butter over medium low heat. Add chopped onion, mushrooms, and chopped green bell pepper. Cook, stirring frequently, for 3 to 4 minutes, or until onion is softened and mushrooms are browned.


Add skillet mixture to macaroni with chopped olives, shredded cheese, sour cream, salt and pepper, chicken, and milk.


Transfer chicken and macaroni mixture to a shallow 1 1/2-quart baking dish. Sprinkle buttered bread crumbs over the top of macaroni and chicken casserole.


Bake at 350° for 25 to 35 minutes, or until chicken casserole is bubbly and breadcrumbs are lightly browned.


Serves 6.