1 lb. frozen haddock fillets
1/4 c. finely chopped onion
1/4 c. butter
2 tbsp. all-purpose flour
1/4 tsp. salt
1/8 tsp. pepper
1 1/2 c. milk
1 c. shredded sharp American cheese (I use cheddar) - 4 oz.
1/2 c. sour cream
1 c. frozen peas, thawed
1 (4 oz.) can mushroom stems and pieces, drained (I use fresh, just saute a little)
1 1/2 c. soft bread crumbs

In a large skillet barely cover haddock with water. Simmer gently until fish flakes with a fork, 12-15 minutes. Drain. Break fish into large chunks; set aside.

Meanwhile in large saucepan cook onion in 2 tablespoons of the butter until tender but not brown. (You can add the fresh mushrooms to this.) Blend in flour, salt and pepper. Add milk all at once. Cook and stir until thickened and bubbly. Remove from heat. Add cheese; stir until melted.

Stir in sour cream, fish and peas and mushrooms if you use can.

Turn into 6-8 ounce shallow casseroles. Melt remaining butter; toss with bread crumbs to combine, sprinkle atop casserole.

Bake uncovered at 400 degrees for 15-20 minutes. Garnish with fresh parsley and paprika.

I bake it in a 13x9x2-inch baking dish.