Recipe

1. Place fish in a well-greased 13- x 9- x 2-inch baking pan; pour 3 tablespoons melted butter over fish. Combine water and lemon juice; pour over fish. Place onion on top of fish. Cover and bake at 350° for 30 minutes or until fish flakes easily when tested with a fork. Transfer fish to a serving platter, and keep warm. Reserve pan drippings.

2. Melt 2 tablespoons butter in a heavy saucepan over low heat; add flour, stirring until smooth. Cook 1 minute, stirring constantly. Gradually add reserved drippings; cook over medium heat, stirring constantly, until thickened and bubbly. Combine yolk and whipping cream; gradually stir into sauce. Stir in salt and pepper. Cook until sauce is thoroughly heated.

3. Pour sauce over fish on platter. Garnish with parsley sprigs and lemon wedges. Serve immediately.