The cherimoya is the finest fruit of all the Annona species (the writer's opinion) and considered one of the most exquisite fruits in the world. Mark Twain once called cherimoya “deliciousness itself”.

Cherimoya are a special kind of fruit called a syncarpium, where several pistils are fused together and united into a single mass along a central receptacle. The primitive fruit form has spirally arranged carpels, resembling a raspberry, with each segment of flesh surrounding a single hard black seed. Fruit size is generally proportional to the number of seeds within.

The subacid flesh is creamy white, soft, juicy, sweet and very fragrant, with a custard-like consistency. The flavour is rich and aromatic, a blend of sweetness and mild acidity resembling a cross between banana, passionfruit, papaya and pineapple.
Cherimoys come from South America. They are generally shipped to stores a bit on the hard side, and if you cut them up while still hard they taste like pine trees (my opinion from experience). However, if you let them sit on your counter for 3 days or so, they become very soft. If you gently squeeze it and you think it's too soft, it's not. it's just right. It should be soft.

Here in the USA they are kind of expensive ($6-$7 / lb) but one generally goes for $3 or $4, and I can eat it all in about 2-3 days, unlike an apple that you eat in one sitting, so that makes it more worth the price, but the taste (to me) is so good that it's worth it. It's like a banana meets vanilla ice cream, and maybe a mild pineapple taste is in there as well. It has a lot of medium-sized black seeds (a lot like watermelon seeds) so watch out for those while eating it.

If you can find these fruits, pick one up.