First off, you should know that chayote is reported to have magical powers. But more on that later.
Chayote is a member of the gourd family of plants, so its kin include squash, cucumbers, and melons. And "chayote" is just one of many names for this food--there are at least 20, including pipinola, sousou, vegetable pear, is-kush, and cho-cho. So, to use a very obscure horror movie comparison, you could say that chayote is "The Living Dead at the Manchester Morgue" of food names.
Chayote is originally native to Mesoamerica, but it has spread over almost the entire globe. It's enjoyed in both North and South America, Europe, Asia, Africa, and Australia. So, essentially, save for maybe the scientific outposts in Antarctica, pretty much wherever you live, people are probably eating chayote fairly close by. It's consumed in a variety of ways, too. Some enjoy it raw and in salads, and other folks like it boiled, baked, fried, pickled, mashed, or stuffed. Most commonly, though, it's cooked and served as a side dish, or mixed in with other foods, such as meat.
The one I bought was from Costa Rica, which is a large producer of chayote. They're fairly weird looking--about the size of a pear, with a pear-like light green color. Mine had a bizarre cleft at its base. Which, depending on your maturity level, either looked like a mouth or a butt crack.
I started by cutting off a piece (there's no outer skin or rind to peel) and trying it raw. And I have to agree with the general assessment--raw chayote is pretty unpleasant. Somehow kind of tasteless and nasty at the same time. Therefore, I broke my normal habit and did some cooking. I chose a recipe that both showed up on the first page after I googled "chayote recipes," and one that promised a short cooking time. Here it is, roughly:
Ingredients: Chayote, olive oil, garlic clove, salt, pepper, and wine vinegar.
Directions: 1) Cut up chayote into narrow, bite-sized strips.
2) Cover bottom of medium-sized skillet with olive oil and put on low heat.
3) When oil is hot add chayote, salt and pepper to taste, and garlic. Stir and cook on medium heat for about 5-6 minutes.
4) Add vinegar and cook another 4-5 minutes, until chayote is slightly wilted but still firm.
5) Taste, and add more spices as needed.
I should mention I used garlic powder instead of a clove, and white vinegar instead of wine vinegar. I also cooked it longer than the original directions, as I thought the chayote needed it.
Anyway, I thought chayote was alright. It's very squash-like, only perhaps a little blander. I found ketchup really improved its flavor, although for what it's worth I think ketchup improves many, many foods. Chayote made for a decent side dish. Since I got this at the Union Market in Washington, D.C., and I've never seen it sold elsewhere, I probably won't have frequent opportunities to have it again. But if you get the chance, and especially if you can find it at a restaurant (probably a Central or South American restaurant will be your best bet) it's not a bad choice, especially if you're a squash fan.
On to the alleged powers. Up in the mountains of Columbia, there's a small town named San Bernardo. In the 1950's a flood washed through, which was destructive enough that the locals had to move a local cemetery. During this removal, they discovered something strange--many of the bodies were mummified, with particularly good skin preservation. Some of these mummies were put on display, and they became a tourist attraction. Many of the people in San Bernardo think that the mummies are so well preserved because of the local diet, which is heavy on the chayote. (Skeptics point out that the town's altitude, and local climate are probably the real factors. Among other things, they mention that the bodies' clothes are also well-preserved. It seems dubious than any consumed food would also cause your burial outfit to survive, too!) Oddly, I couldn't find any claims that the chayote causes smooth and beautiful skin among the living in San Bernardo, only the dead. So even if their chayote explanation is true, it seems like a fairly useless gift, even more so if you opt for cremation of your earthly remains. But, if there is ever a worldwide zombie apocalypse, at least the citizens of San Bernardo can take solace in the fact that they will be eaten by unusually attractive reanimated corpses.