If your cookie sheets or other bakeware get like mine do when I’m in a rush and don’t have time to properly clean them (that’s most of the time), there are two easy methods for getting them in better shape. They might not look exactly like when you first purchased them, but on the other hand, you won’t have to hide them either.
First try using a paste of baking soda and 3% solution hydrogen peroxide, which is the strength sold in most stores. Mix this up – you can even do it in the sink itself – and then let the item sit covered with plastic wrap or a rag for a few hours. Then just rinse it. Most of that dark brown stuff should be gone.
Otherwise If that doesn’t work well, fill the sink with water and drop a couple of denture cleaning tablets in (I’ll talk another time about all the problems that these tablets solve too and it’s worth buying them even if it’s just for cleaning). Again let the item sit for a few hours and then rinse thoroughly.
If you have allowed the stains to get really baked on, It might take a few times of soaking in order to get rid of most of the crud. However it sure beats throwing them out and buying new when you are too embarrassed to let anyone see them. That’s bad for the environment and for your budget too!