The Chayote (Sechium edule) is a gourd native to Mesoamerica but grown world-wide. I actually came across my first plant in Vancouver. Many houses grow them on trellises in their front yards. The root stalk is borderline hardy there depending on the severity of the winter, so it's probably a tender perennial in zone 7. At the time, I had no idea what the plant was. I just seemed like another random gourd. However, after getting back to London, Ontario I discovered them for sale at Asia Food Mart.
I asked someone working there about the chayotes and she suggested I make them into a soup. The soup was absolutely delicious! I'll be sure to post the recipe next time I make it (probably later this week). I loved it so much that I decided to plant some seeds. Each Chayote comes with a large edible seed in the centre. In many cases the vine has already started growing out of the fruit when you purchase it.
Now they normally tell you to plant the fruit whole, but I really like the soup. I basically cut about 1cm around one seed and planted another one bare. The bare one never sprouted but the one with fruit has turned into a little vine. Growth has been slow to start but I expect it to speed up. I'm in zone 6a so I'm hoping if I cover it up for the winter the roots will survive. It's probably to late to expect any fruit this year.
I highly recommend you try Chayote if you can find one. You can even eat it raw and chop it for salads. It almost tastes like a less intense pear/apple cross with a similar texture. I'm thinking the summers here may be a bit too warm (bordering on 30C during the day). There's only one way to find out. Hopefully by this time next year I'll have baby Chayotes covering a vigourous vine!