That's got to be one of the worst clues I've seen for a long time! Apart from the meaningless surface reading, the position of the "sounds like" is unhelpful, suggesting the potatoes are the homophone rather than the answer. And with equally unhelpful checking letters, I'm not surprised you didn't get it, Dandy. I'm not sure I would have either.
I used to do the RT puzzle before I left the UK in the mid-2000s, and I'm sure the clues were of a higher standard than this.