we have a lot of atis trees in pampanga. atis--latin name: annona squamosa, aka custard apple, sugar apple, or sweetsop--is the most widely grown of the annona varieties, which include the well-known cherimoya. its origins are unknown, but the spaniards most likely brought from south america and introduced it to southeast asia sometime before 1590.
the fruit is usually 2-4 inches (6-10 cm) long. it is covered in a dull greenish rind and is composed of knobby segments, which break apart easily when ripe. the pink-around-the-edges creamy white flesh surrounds dark, glossy inedible seeds. the soft, scoopable flesh is often compared to a sweet custard in texture and taste, and is best eaten fully ripe and fresh; however, freezing the fruit will yield an instant, portable, creamy, fruity 'sherbet' that is most welcome on hot summer days.