Are you talking about prickly pear? I tried them once before in homemade sorbet, don't ask, I had a wild hair I guess! The flavor was very bland, all you could really taste was the sweetness of the sorbet. It was an amazing color though and it stained the hands of my husband and I for a few days, they are a challenge to seed.

This is the fruit that I'm talking about: http://www.wikihow.com/How-to-Eat-Prickly-Pear-Cactus