How to remove image files from sprockets cache?

[jheasly]

ruby noob here. There's apparently some caching going on so that removing image files from source/images gets middleman/middleman-sprockets all upset. I can't find anyway to appease them/it other than returning the unneeded images to the directory.
Is there a way to turn this behavior off?

[NickSiena]

https://stackoverflow.com/questions/9246585/how-to-clear-sprockets-cache