Plunge live lobsters head first into enough boiling, salted water to cover.
Bring to boiling; reduce heat and simmer 20 minutes.
Remove at once.
Place on backs on cutting board.
Cut in half lengthwise: draw knife from head down to base of abdomen.
Discard all organs in body section except brownish green liver and red coral roe (in females only).
Remove black vein.
Crack large claws.
Remove meat from body and claws.
Clean and reserve whole shells.
Coarsely chop the meat.
Add the 1/2 cup melted butter, sherry, onion, salt, garlic powder, and dash pepper.
Stir in mushrooms, roe, and liver.
Stuff shells with mixture.
Combine bread crumbs and 1 tablespoon butter.
Sprinkle over stuffing.
Place in shallow baking pan and bake at 350° for 30 to 35 minutes.