Worst of all in this regard are the charred edges of a delicious lasagna, or the charred crumbs left behind when the plate is put back in the oven and then forgotten. Worse than that is my personal favorite - sausages grilled in a honey marinade - (well, I'm a beekeeper too).
Faced with this situation, first use a kitchen towel to wipe off anything that goes easily. Then put a cup of baking soda in some very hot water and soak the pot in it for up to an hour. If that doesn't work, do it again, but just add sea salt to the mixture and make sure the pot is fully submerged. Some people add a third ingredient (vinegar), but it's not really necessary. This process will really loosen the "stuck" bits. Once they're loose, sponge or scrub the plate (depending on its surface) until it's clean, then dry it carefully.
If all else fails, why not get yourself a new tray or plate? Visit our ovens