A can of peanut butter spilled some of its oil onto the carpet causing a dark stain. I scrubbed it immediately but it didn't come up. After Googling the problem, I tried putting baking soda on the stain, letting it set and scrubbing with dish soap, but that trick didn't work either.
It's now set into the carpet and seems to be with us permanently. Is there any way to remove a set in oil stain from carpeting?