For future - use parchment paper to keep pans clean.
Hi GEnie: What I use is a paste of vinegar and cream of tartar (the dry stuff). Make a paste and put it on the gunk. Let it sit for about 15 or 20 seconds and then scrape off with a plastic putty knife or one of those plastic scrubbies. You may have to do it a couple of times if the gunk is thick, but usually not. There is no smell and it is environmentally safe. Good luck.
Ken - can you put parchment paper under things cooked at high heat like pizza? Can it be used under the broiler? (I don't think so lol! 😎)