Circles. Only two colors of icing. I can do that! Nice and easy.
The process still takes several days because of cooling and drying times. Day one was baking, day two was outlining and flooding with white icing and day three was adding the red stitching detail.
I'm not very good at consistently drawing curves with icing, so I used the round cookie cutter as a template. I traced a curve on to the dried white icing with a toothpick and then drew with the red icing on top of the toothpick mark.
It worked better if I let the red curved lines dry a little bit before adding the red stitches. Otherwise, the stitches kept sticking to (and moving) the red lines.