Sechium edule is a member of the Cucurbitaceae (gourd) family, but is referred to variously as a fruit or vegetable.
Well, there's its Latin name. The mirliton (MER-lit-awn) or (MEL-it-awn) is also known as the chayote squash, or vegetable pear in America, and by a host of other names throughout warm climates everywhere. It was brought to bayou country by the Canary Islanders, who relocated to Louisiana when Spain took ownership of New Orleans from France; they called it "mirliton". It was also domesticated by the Aztecs, who called it "chayotl". It is "christophine" or "brionne" in much of the West Indies, "chochoute" in Madagascar and Polynesia, "xuxu" in Brazil, "hayao uri" in Japan, "tao tah" in the Hmong tongue, and "chocho", "custard marrow", "pepinella", and more names throughout the world.
It is a pear-shaped squash with thin green skin, crunchy but very sweet white flesh, and edible seeds. I had never heard of it until I bravely ate one stuffed at NOLA, Emeril LaGasse's restaurant in the French Quarter of New Orleans, which happens to be mirliton's home turf in America. It was delicious and sweet, and I had it baked, stuffed with crawfish and shrimp with sweet potato shoestrings and a light cheese sauce. It cost about $8.00, and would make a nice lunch by itself--it was delicious and worth it.
Most recipes for mirliton follow this vein; everywhere I looked, I saw recipes for mirliton stuffed with this or that. The soft, sweet, neutral flavor and rich texture makes it ideal for stuffing. Other approaches include baking it whole and eating it alone, but references also note that it can be served creamed, buttered, fried, frittered, boiled, mashed, pickled, in salads, in soups and stews, or in pies. In many countries the young shoots, flowers, seeds and roots are frequently eaten.
The flesh of the mirliton is nutritious and low in calories and sodium, and can frequently substituted for (or supplanted by) summer squash in dishes when one or the other is not available.
mad props to http://www.rain.org/greennet/docs/exoticveggies/html/chayote.htm , among others.