Cut bread into halves lengthwise. Hollow out the halves, reserving bread removed and the intact shells. Crumble enough of the reserved bread to measure 1/2 cup. Put bread shells cut side up on baking sheet. Sauté onion, celery and garlic in butter in sauté pan until onion is translucent. Add shrimp, Old Bay seasoning and crab boil and simmer for 3 to 4 minutes or until shrimp are cooked through. Add green onions and crumb in reserved 1/2 cup bread. Stir in cream. Spoon mixture into bread shells. Sprinkle with the cheese. Bake at 350 for 10 minutes or until cheese melts. Let stand for 5 minutes. Cut into pieces to serve as an appetizer or into halves to serve with a green salad as a main dish. Serves 8 as an appetizer or 4 as a main dish.