There is a right and a wrong answer to this question.
Many people know how to say “Reese’s.” Many other people appear to have not a damn clue how to say it. Which are you?
If you disagree with my objectively correct and scientifically unbiased conclusion, I have a simple rebuttal for you: Reese’s Pieces. It rhymes. The entire point is that it rhymes. Why would that name exist if it wasn’t supposed to rhyme? What is wrong with you, you horrible monsters. Still, take heart! Even if you are tragically unskilled at candy nomenclature, take solace in the fact that it could be worse; you could be one of those horribly broken people who refer to all sodas, regardless of brand, as “coke.”*
Meanwhile, the Jezebel staff was almost (almost) uniformly well-versed in peanut butter cup pronunciation protocol. Bobby had an interesting theory: