Sausage Stuffed Mushrooms

12 to 15 large fresh mushrooms
2 tablespoons butter or margarine, divided
2 tablespoons chopped onion
1 tablespoon lemon juice
1/4 teaspoon dried basil
salt and pepper to taste
4 oz. bulk Italian sausage
1 tablespoon chopped fresh parsley
2 tablespoons dry bread crumbs
2 tablespoons grated Parmesan cheese

Remove stems from the mushrooms; set caps aside. Finely chop stems; place on paper towel and squeeze to remove any liquid. In a skillet, heat 4-1/2 teaspoons butter. Saute stems and onion until tender. Add lemon juice, basil, salt and pepper; cook until most of the liquid has evaporated. Cool. Add sausage and parsley. Stuff into the mushroom caps. Combine crumbs and cheese; sprinkle over stuffed mushrooms. Dot each with remaining butter. Place in a greased baking pan. Bake, uncovered, at 400 degrees for 20 minutes, basting occasionally with pan juices. Serve hot.