Puzzle pieces are a bit of a piping challenge, but I think they turned out OK.
If I were younger and wiser, I may have opted for a more simple, yet equally tasty, decoration demonstrated below. I like the pre-bite. Just to be sure this cookie is worth decorating in the first place. :)
Or maybe even skip the frosting entirely and just enjoy the cookie plain, like Devin Jordan.
The kids also made me this adorable thank you card. They're the best!