One of my wooden spoons has mould on it (black spots, not able to be removed by surface scrubbing - I went on holidays without clearing the dishwasher...).
Is there a way to remove the mould? Or should I just buy a new wooden spoon?
If its soaked in the spoon, I'd not risk it for an inexpensive wooden spoon. A soak in a bleach solution is the common treatment though. I'd buy a new one or replace it with a high temp silicone spoon (no unremovable mold issues in the future then!)
rfusca raises a good point - if you're worried that it's actually penetrated deep, you might just replace it.
That said, I'd just use sandpaper. Hopefully it's just a surface stain, and you won't have to take much off, but you'll be able to see how deep it's gotten as you go!