Au Gratin Fish Supreme - cooking recipe

Ingredients

1 Tbsp. plus 1 tsp. reduced-calorie margarine (tub)
1 c. sliced mushrooms
1/4 c. diced onion
1 Tbsp. plus 1 tsp. all-purpose flour
1/2 tsp. salt
dash of pepper
1 c. skim milk
1 (9 oz.)pkg. frozen French-style green beans, cooked according to pkg. directions
4 oz. cooked cod, haddock, flounder or scrod fillets
1 (2 oz.) English muffin, split in half and toasted
2 oz. Cheddar cheese, shredded

Preparation

In 10-inch nonstick skillet, heat margarine until bubbly and hot; add mushrooms and onion and saute until onion is translucent. Sprinkle vegetables with flour, salt and pepper and stir quickly to combine; cook, stirring constantly, for 1 minute.
Continuing to stir, gradually add milk and bring just to a boil.
Reduce heat and let simmer until mixture is smooth and thickened, stirring frequently.
Stir in green beans and fish and cook until fish is heated through.
Set each muffin half on a flameproof plate; top each half with half of fish mixture and 1 ounce cheese.
Broil until cheese is melted and lightly browned, about 1 minute.