several have asked for directions on making this tacking stitch. i have heard it called by several names.
when the needle travels from the bottom of the vee to the next position to begin the next stitch it is traveling thru the batting. the only portion of this stitch that shows on the back of the quilt is the right leg of the vee. i have circled it in the first illustration.
any questions just ask.
have fun,
marie