Turns out, temperature fluctuations in the kitchen had caused the plastic lid on the cocoa box to relax. The lid no longer fit the container. When I was done cleaning cocoa off everything, I put what cocoa was still in the container in a canning jar for fresher - and safer! - keeping. But I'm a busy mom - plus I'm nearing menopause - so I knew I'd forget what was in the jar...unless I labeled it.
It's not uncommon for me to put homemade condiments or store bought stuff that takes up too much room in a box in a canning jar. And, like I said, it's always best to label them or my hair-brain will never know what's inside. (Sweetened cocoa? Unsweetened? Who knows!) Since I'm frugal, I don't like to use new, unused canning lids for this purpose. Instead, I use canning lids that have come off home canned goods. I run them through the dishwasher, and they are perfect for storage purposes.
I don't like to keep a ton of them around, though, or they get in my way. (If food flies out of my cupboards, imagine what would happen with a drawer full of used canning lids!) So I keep only a handful. And I've found an easy way to remove the writing from these lids, so I can neatly and easily write on them again:
Just dip a Q-tip (or the corner of a towel) in some rubbing alcohol and rub it over the pen markings on the lid.
They come right off. The lid dries in a few moments, and you can write on it again.
Easy! And when you're a harried mom with food flying out of the cupboards, easy is very, very good.