I normally wipe it clean straight after use and can easily get it completely clean. Today I didn’t have time to wipe it straight after use, so wiped it a few hours later, by which time the melted mozzarella had dried onto it. I’ve wiped it lots of times with hot water and washing up liquid, and left the water and walking up liquid on it for a while, but it’s still not totally clean. Any ideas for how to clean it without damaging the non-stick surface?!