Stamps are by Red Rubber Designs who bought out TAC products after it closed in 2011. I colored the image with Copics.
Here you can see the technique a bit better. I love sunflowers and have numerous stamp sets from assorted companies. One of my other favorite companies is Heartfelt Creations. We are getting some wildflowers growning here in southern AZ. The wild poppies are all over! And my rose, geraniums, and daisies are going crazy in their pots.