The outsides of the bag were made with pieced strips, in a quilt as you go fashion.
Here's a progress shot of some of the work done that day, by the ladies participating.
I made my bag later. I had the parts of 2 blocks left over from making Lug Nuts, the pattern suggests you can piece them into the backing, but I had a wide back and wasn't needing to piece it at all, so I still had the blocks, and thought to use them in this bag. I finished piecing the blocks in a quilt as you go fashion, and framed them out to make the hexagons rectangular, again in a quilt as you go fashion. Between the fusible fleece and the seams sewn, there was enough stitching to hold everything in place--but where's the fun in that for a quilter? and so I loaded the panels on my longarm and quilted them.