Stella knows the container where we keep our cookies. The empty container was on the counter, waiting to get washed, so she flew over and tried to open the cover. Since she is not delicate (I can't really blame her since she's using a beak instead of hands to open it), I opened it for her to show her that her efforts would be in vain -- we'd eaten all of the cookies. I expected her to fly back to her stand, but I was wrong.
I underestimated her longing for cookie crumbs, as she immediately jumped up to clean up: