Go to Wikiart (one of my favorite sites), click on "Artworks," and choose "Random artwork."
You are only allowed to do this once. The challenge comes from working with whatever you're given.
Set your timer for fiften minutes and write a scene that takes place inside that painting.
It may seem impossible at first. Keep going.
The story may seem too obvious at first. Keep going.
Don't stop putting words on the page until the timer goes off.
P.S. The words don't have to be brilliant. They don't even have to make sense. If you keep going—writing anything—for fifteen minutes, you've succeeded.
Here's the painting I got:
|Pierre Bonnard, Night Landscape, 1912|