In a medium saucepan, cook the mushrooms, onion, celery, green pepper, and garlic in margarine or butter until vegetables are tender.
In a 2-quart casserole combine the cooked wild rice, vegetable mixture, almonds, cheddar cheese, and pepper.
Cover and bake in a 325 degree F oven for 40 to 45 minutes or until casserole is heated through. Makes 8 servings.