Tuna Mushroom Casserole

1 pkg. (12 oz.) wide noodles, cooked and drained
2 cans (6 oz. each) tuna, drained
1 can (10-¾ oz.) cream of mushroom soup, undiluted
1 1/3 cups milk
½ tsp. salt
¼ tsp. pepper
½ cup crushed saltines
3 tbsp. margarine, melted
paprika, tomato slices, and fresh thyme

In a large bowl, combine noodles, tuna and mushrooms. Combine soup, milk, salt, and pepper; pour over noodle mixture and mix well. Pour into a greased 2 ½ quart baking dish. Combine saltines and margarine; sprinkle over noodles. Bake, uncovered, at 350 degrees for 35-45 minutes or until heated through. Sprinkle with paprika and garnish with tomato and thyme.