My favorite cookie cooking tip

So when I first met my soon to be brother in-law, he came in with a big plate of yummy chocolate cookies.  The best part, he made them himself and they were cooked to perfection!  Now I did worry a pinch here (just kidding Chuck! ;).  Anyways, I asked what the secret was as I am an awful cook and my cookies always have crisp edges.
The secret was.......take them out just before they are done and let them sit on the warm pan for another 5 minutes.  Such a great trick and has worked every time!