Half fill it with water, then put in on the stove top over a medium heat.
Work
the burnt-on bits with a wooden spoon or spatula as the water starts to boil.
You should be able to soften it up and be able to get it off then.
cooking.stackexchange.com/users/210/Sam Holder
Ammonia does a really nice job on pans with a lot of burn on black debris that won't come off with scrubbing.
Remove the bulk of the debris on thepan,(you're already there)
Then place the pan, and a containerwith
some 1/2c(120ml) of householdammonia in a plastic bag.
Close up the bag (doesn't have to be totally airtight).
Leave
it sit for several hours toa couple days.
The burnedon stuff will come off pretty easily.
Then wash the pan normally.
I strongly advocate letting the pan/bag combination sit outside or in a garage or very well ventilated room during the soaking phase.
This works great on broiler pans, but I have used it on other pans as well.
Do NOT use this technique on aluminum pans.
cooking.stackexchange.com/users/2045/Laura Thomas
There is a special tool that I use for tough pot cleaning jobs.
It is a small hard nylon square, with three curved corners and one more pointed corner.
The edges are slightly beveled.
I have several that came with my order of pampered chef bakeware.
I think you might be able to buy them retail or online also.
cooking.stackexchange.com/users/1184/mamadalgas
There's not much to say about this: The only thing you can try is to use fat-resolving detergents.
The rest that is really burnt to coal has to be removed physically by hand.
No way around this, unfortunately.
cooking.stackexchange.com/users/3144/RBloeth
I managed to clean a roasting tray with some icky sticky grease solidified on it that simply wouldn't come off.
I put it under the grill for 10-15mins at 220degC, then took it out and placed it in my steel sink then (carefully and with one hand in an oven glove!)
I put a small amount of washing up liquid on and scrubbed it with a steel wire scourer .
The grease, which now seemed to have been burnt by the heat came off very quickly.
Obviously this comes under the "don't try this at home kids" but I didn't need any potent cleaning products.
cooking.stackexchange.com/users/41847/mungflesh
Baking Soda and vinegar made to a paste, use paste to buff pot or pan with a soft cloth.
Works like magic.
cooking.stackexchange.com/users/16855/something new
I made  this recipe  last week - chicken wings roasted in a marinade of soy sauce, brown sugar and white wine vinegar. It was delicious but lots of the marinade has burned onto my baking tray, and I'm struggling to get it clean.   I put it in to soak immediately, scrubbed and then tried washing powder, but it is still very firmly stuck on. Does anyone have any cleaning ideas that might help me in this case?
What is the best way to clean a roasting tray/baking tray that has sauce burned on to it?
cooking.stackexchange.com
<equipment><cleaning><roasting>
cooking.stackexchange.com/questions/8968
cooking.stackexchange.com/users/2065/Bluebelle
You can scrub it with washing up liquid, a paste of baking soda and vinegar, ammonia or other fat-dissolving detergents. You could also try adding some water and putting it on a stovetop over a medium heat. Try using a detergent specifically for grease. You can also heat it up with a little water on the stove or use a steel wire scourer.
Try using baking soda, ammonia or a degreasing detergent. Fill with a little water and heat on the stove to loosen the dirt. Scrub with a steel wire scourer.