In a large bowl, place the cubed stale bread. Pour the water over and let soak for 10 minutes. Sprinkle the salt, garlic salt, black pepper, red chile flakes, crab boil seasoning, chopped celery, and chopped onions. Using your hands, combine all the ingredients together into a homogenized mixture. Set aside so the flavors blend.
In another large bowl, combine the bread crumbs, crab meat, and crab sauce. Mix into a homogenous blend.
Take a small handful of the bread mixture and using your thumb or finger, press out a hole. Take a small scoop, about 1 1/2 ounces, of the crab mixture and place it into the hole. Bring the bread mixture around the crab mixture, forming a patty. Set aside on a sheet pan lined with parchment paper, or a large platter. Continue making patties until all of the mixtures are used.
In a large skillet, pour 1 1/2 inches of oil into the pan. Heat the oil to 375 degrees F., or until a small piece of the bread mixture sizzles and bubbles when placed in the oil. Place patties in the pan, being careful not to crowd them. Fry until golden on 1 side, about 3 to 4 minutes, and then flip over and fry until golden on the other side.
Note: This recipe was provided by professional chefs, and therefore may be difficult to reproduce in the home.
In a large sauce pot, combine all the ingredients. Cook over medium heat, at a simmer, for 30 minutes. Chill the sauce before using.