Three years ago, if you saw a cherimoya, it had almost certainly been flown in from Chile or Peru and had been languishing in the "exotic" produce bin at the supermarket, waiting for someone to recognize it and pay $5 for a tiny, withered fruit.
Commercial production of cherimoyas has finally come to Southern California, and the fruits are all over our farmers' markets. The fruits look like scaled, pebbly avocados, but inside the flesh is creamy white. The riper the fruit gets, the more custard-like the flesh gets. Most cherimoyas are eaten fresh, but they might make outstanding frozen desserts or agua fresca.
Ripe cherimoyas give slightly to pressure, like avocados. As with just about any fruit, avoid cuts that pierce the skin, mold or excessive browning. Just cut it in half and scoop it out with a spoon. Don't eat the black seeds.