I specifically got stainless steel fry baskets to go in there because I cannot bring myself to trust Teflon anymore. Besides the sense of risk, it just wears out so fast it's like I rented it. I'm all stainless, tempered glass, and cast iron these days. And you can scrub the shit out of those.
It depends on what it's made of. If it's still you can soak it in lye water, or use easy off oven cleaner. It'll tear apart the burn spots in the organics and leave you with bare metal.
The tricky part, is if it's aluminum. It'll actually corrode the surface. All the organics will still come off of it, but it will leave a black oxide coating on the surface. Now to be fair that Black oxide coating is easier to scrub off then the original grease carbon, and polymers, but it will leave the surface a little thinner and a little pitted. If you do it more than a few times on thin aluminum you can actually put holes in it.
The next best thing to use would be bar keepers friend which is an oleic acid powder cleanser it requires quite a bit more elbow grease but it will get the job done without hurting the metal.
Spray it with easy off let it sit for a few minutes if it is steel you'll just be able to scrub it clean without too much work. If it turns dark gray it's aluminum just scrub it down wash it off scrub it down again wash it off again.
Is it coated with anything? If it's just bare metal then scrub it with steel wool and some water, any burns & stains should come off without much effort.
If it's coated then I'd try to soak it in soapy water over night and then gently scrub. Keep in mind that anything you put on there you're probably going to eat with your next few meals so before you use any aggressive chemicals just buy a new tray.
To add to this, you can get scrubby pads that are plastic and wonโt scratch Teflon or other no. Stick pans. Just make sure theyโre not doped with abrasive paste.
Soak with some dish soap, anything more than that is going to be problematic. This