Paprika Oven method: (27 minutes cooking time) Melt butter in small skillet over medium heat, about 1 minute, add onion, green pepper, and celery. Saute' until tender, about 6 minutes. Combine onion mixture, cream cheese, bread crumbs, salt, pepper, lemon juice, and worcestershire sauce in bowl. Mix well. Fill mushroom caps heaping full of mixture. Place in greased 8 inch square baking pan. Sprinkle with paprika. Bake in 350-degree oven for 20 minutes. Serve with coctail picks.