A peanut butter jar isn’t usually fun, but it is if you put it outside and watch what squirrels do with it. The smell drives them crazy, and exterminators use peanut butter bread in live traps when squirrels get in attics. (Been there, know that, years ago, attic eave problem fixed, lol.)
I’ve seen one put his whole body down in the jar, then scoot it across the grass with his back feet, trying to get the peanut better out of the bottom. Also have seen them try to chew thru the bottom cos they could see a little peanut butter left in there.
If you have squirrels and put a jar out for them, you won’t have to wait long to see what they do.