The present invention comprises an improved extruder die assembly and method for using same to improve the quality of dimensional design aspects of extruded, complexly shaped, direct expanded food products. The improved system includes an improved extruder die assembly comprising a transition insert section, a plurality of spacer insert elements, an imprinting insert element, and a forming insert element, all of which are coaxially aligned and interlocking. The improved extruder die assembly of the present invention is designed for adaptation to a wide variety of commercial-grade extrusion devices (e.g., twin screw, single screw, forming extruders, and pasta extruders) common in the food industry.