Pour chicken fillet with cold water, bring to a boil. Remove foam with a slotted spoon, salt, reduce heat and cook under a loosely closed lid for 20 minutes. Remove the meat, cool. Cut the chicken fillet and pickles into strips.
Peel the celery, cut into thin strips, place in a colander, immerse in boiling salted water for 3 minutes.
Cut the bread into small cubes. Fry in vegetable oil until golden brown, 2-3 minutes. Stir in fillets, cucumbers, and celery. Season with mayonnaise. Serve the croutons separately.