In small bowl combine flour, celery salt, and garlic salt.
Add oil and milk all at once; stir with fork till well mixed.
Form into a ball.
Place between 2 sheets of waxed paper.
Roll out to a 10-inch square; remove paper.
Brush with egg white.
Sprinkle with sesame seed; press in lightly with rolling pin.
Cut into 2-inch squares or diamonds.
Transfer to an ungreased baking sheet.
Bake in 450° oven about 8 minutes or till lightly browned.
Serve warm or cold.