Prepare the lobster meat (if uncooked). Bake in a 350-degree oven for 10 minutes. Chop into small pieces.
Mix the lobster pieces with all other ingredients (except the butter) to make a moist stuffing. Add more broth if needed.
Divide the stuffing in half and pack each half into the mushroom caps.
Brush the tops lightly with melted butter. Use any remaining butter to grease the baking dish.
Bake at 375 degrees for about 20 minutes or until the tops are browned.