Oysters Rockefeller

1 (10 ounce) package frozen chopped spinach
1/2 cup butter, softened
1/4 cup cracker crumbs
1/2 cup bread crumbs, divided
6 scallions, finely chopped
2 ribs celery, finely chopped
1/3 bunch parsley
1/3 head lettuce, shredded
Dash Tabasco