Replace "[SCREEN_NAME]" with the actual screen name and, voilà.
EX: <img src="http://api.twitter.com/1/users/profile_image/sdesapio">
IMPORTANT: Make sure the replace [SERVER_NAME] with your real server(machine) name.
Done. Let me just say that I've actually seen people ask how to accomplish this task, only to be told, "It's a waste of time. Why would you ever need to do such a thing?!?! Just blah blah blah..."
Well first off, I don't know about you, but I like my dev environment to resemble, as closely as possible, my production environment. Second, this step is ABSOLUTELY CRITICAL when writing, testing and deploying ANY process that requires SSL. If you think it isn't, come back here when you finally figure it out and apologize.