Roll the croissant dough into a rectangle 5 by 36 in/13 by 91 cm. Trim the edges so they are even. Cut the dough into twelve uniform 3 by 5 in/8 by 13 cm pieces.
Working one at a time with the short edge of the dough facing you, brush the bottom half of the rectangle with egg wash. Place 2 chocolate batons about ½ in/1 cm from the top of the dough. Roll the top