Recipe for Creamy Broccoli & Tuna Chowder

1/2 c. chopped onion
1/4 c. chopped celery
1/4 c. margarine
2 1/2 tbsp. flour
1 1/2 tsp. salt
1 tsp. pepper
3 c. milk
1 (10 oz.) pkg. frozen broccoli
1 can tuna fish
1 (8 oz.) carton sour cream

Saute onion and celery in margarine in saucepan. Stir in flour, salt and pepper. Add milk and make a sauce. Meanwhile, cook broccoli until tender. Add to sauce along with the tuna. Heat through. Add sour cream. Heat through, but do not let boil. Can add more milk, if too thick.