Anybody familiar with a white-to-whitish zucchini that's common in north-north-east Mexican cooking? Not sure if it qualifies as an heirloom, but it is a sort of regional thing. Appears in Mexican groceries here in Columbus, Ohio pretty often. I'd really like to secure some for my friend from Chihuahua who likes to use it in her oxtail soup, amongst other things. She assures me it's firmer and tastes lots better than our all-green ones.