If you know French, you'll probably guess the origin of the name of one of my favorite veggies: it was called "chou-chou" and came to Brazil from the French Antilles. By the way, "chuchu" is a term of endearment in Brazil also (check out this painting and you'll see an excellent artistic representation of this). The chuchu (or chayote in Central America) is a vine, and the fruit is green, pear-shaped and kind of fuzzy - it's covered with tiny, non-prickly thorns. In Brazil they seem to grow in every backyard, but in the US you have to go to Latin markets or, if you're in luck, the exotic veggies section of your local grocer.
I love to make potato salads with chuchus and carrots inside, they look so colorful and taste so good. To prepare the chuchus, peel them with a potato peeler, slice them lengthwise UNDER RUNNING WATER. That's important because they are kind of oily and sticky inside (nothing bad, just feels funny, but the cold water will rinse them). Remove the seed - it's soft and white. Put them in a saucepan, covered with water, add a little salt, and simmer until they feel tender. It's important to watch them, because overcooked chuchu turns mushy. Rinse with cold water, cut the slices into cubes and mix in with your potato salad. Or you can serve a chuchu salad. Just prepare a nice vinaigrette and pour over the slices.