A slurry product is packaged into a plastic bag using a modified form-fill-seal apparatus and method of using it. The apparatus has preferably been modified to select the appropriate amount of product slurry by weight. Bags are filled using a dual auger system that includes a bulk auger and a precision auger that fill a bag simultaneously. The augers work together for a first period to rapidly load slurry into a large part of the bag. During a second period, the bulk auger shuts down, allowing the precision auger alone to top-off the bags. The periods are determined either by time or by the volume or weight of the product that has entered the bag.