The present invention relates generally to the field of microstructured fiber technology, and particularly to an apparatus and method of fabricating a flat microstructured fiber. The apparatus comprises means for feeding a preform; a drawing chamber connected to the means for feeding and being configured for drawing the preform; means for collecting the preform drawn by the drawing chamber; and an assembly removably mounted to the means for feeding having a first and a second body coupled to the first body. The method which is a dual-stage drawing process requires the preform and capillary drawn into a flat cane. At the second stage, the flat cane is drawn to form the flat microstructured fiber which exhibits no air hole deformations and achieves an accurate size dimension.