Preparation / Directions:
Trim 6 slices of bread to fit bottom of greased 12x8 baking dish. Butter one side of each slice with 1/2 t butter and place bread in bottom of dish, buttered side up. Mix crab, celery, onion and mayo. Spread over bread slices. Scatter cheese over. Trim other 6 slices of bread and butter them, as above. Place with buttered side down. Mix eggs, milk, mustard and pepper together and pour evenly over casserole. Cover with plastic wrap and refrigerate at least 2 hr.(overnight). Bake at 350 for 35-40 min. or until puffed and light brown. Let cool 10 min before slicing and serving.