I believe you might have seen a chenille quilt? You have several layers of fabric ( flannel works best) that you stack and sew channels about every 1/2 inch on the 45* bias. After the channels are all sewn, the layers are cut between the stitching line but you don't cut the bottom layer. The bottom layer holds the chenille together and the blanket puffs and frays when washed and dried in the machine. Chenille makes a lot of lint in the washing/drying process so clean the lint trap frequently.