Looks to me like you sew strips all around the center square, then snowball two corners. Add one more row of strips around the outside and snowball the same two corners. The rest is sashing and cornerstones.
Chester the Bunny has one without the sashing. Then each block is tipped a different direction. That produced the large square of background fabric.
Last edited by maviskw; 01-07-2018 at 06:51 AM.