We worked in a nice Florida restaurant one winter where this was the most popular item on the menu.
Bone, skin and halve the chicken breasts. Place in a baking dish, but do not overlap. Sprinkle both sides with salt, pepper and lemon juice. Pour melted butter over each piece, rubbing it in with the back of a spoon. Pour sherry over the chicken.
Cover the baking dish with aluminum foil and place in a 400 degrees F oven for 30 minutes. When done, the chicken will be white and spring back when pressed with finger. (Do not overcook, or the breasts will be dry and the flavor lost.)
Pour off the liquid from the baking pan and save. Keep the chicken warm while preparing the sauce.
Cook the butter and flour together for 2 to 3 minutes. Stir in the chicken liquid from the baking pan and the cream. Cook over medium heat until smooth and thick, stirring constantly.
Spread the sauce over the chicken breasts; sprinkle with Parmesan cheese and paprika. Return to the oven and bake until the surface is golden brown - about 5 minutes.