Celery Salad

Peel outer strings from 4 celery ribs with a paring knife.
Cut peeled celery into 2-inch lengths, then use slicer to julienne enough celery to measure 2 cups, reserving all trimmings.
Transfer julienned celery to a bowl and chill.
Cut enough of trimmings and remaining ribs into 1/4-inch slices to measure 2 cups.
Add celery slices (not julienne) and water to a small saucepan and simmer, covered, until tender, about 5 minutes.
Remove from heat and add parsley, stirring until wilted.
Transfer blanched celery slices, parsley, and any remaining liquid to a blender and puree until smooth, about 2 minutes, then force through a medium-mesh sieve into a bowl, pressing on and discarding solids.
Stir 1/4 teaspoon salt and a pinch of pepper into celery coulis and set bowl in a larger bowl of ice and cold water.
Heat 1 cup oil in a 10-inch skillet over moderately high heat until hot but not smoking, then fry bread, stirring constantly, until golden brown, 15 to 20 seconds.
Immediately transfer croutons with a slotted spoon to paper towels to drain, then sprinkle with celery salt.
Cool croutons to room temperature.
Whisk together vinegar, pepper, remaining 1/4 teaspoon salt, and remaining tablespoon oil in a large bowl until blended, then add celery julienne and croutons, tossing to coat.
Spoon about 2 tablespoons celery coulis onto each of 4 plates and pile salad alongside.