When my original plans for a prompt fall through—no matter what the prompt is—I fall back on taking pictures of food. (Or the cat, when she’s cooperative, but that wouldn’t really work for this prompt.)
That said, I’m actually really happy with how this turned out. It’s happened a few times, now: I end up having to improvise, and it creates a photo even better than the one I had in my head.
I need to remember that.