My husband and I ate at Peace Cafe multiple times while in Siem Reap. We're both vegans, so that did limit our options; that being said, though, we definitely felt like there was enough for us to choose from. There were several Khmer options that were vegan, which we really enjoyed.
It's a pretty adorable place, and we really enjoyed hanging out in their garden. The staff was friendly, although they didn't seem to understand when we said we were vegan (the veggie passport was super helpful for that, though!)Pros: Great food, Awesome garden, Friendly staff
Cons: Not a ton of vegan options, Not enough Khmer food.