The cherry stones are cracked to extract the seed kernel, which is about 5 mm diameter, soft and chewy on extraction, but ground to a powder before use.
The flavour is similar to a combination of bitter almond and cherry.
It has been used for centuries in the Middle East and the surrounding areas as a sweet/sour, nutty addition to breads, cheese, cookies and biscuits.
In the United States it has long been a staple in Greek American Christmas cake and pastry recipes.
Thanks to renewed interest in Mediterranean cooking it has been recently mentioned in several cookbooks.
In Greece it is called μαχλέπι and is used in egg-rich yeast cakes and cookies such as Christmas ''vasilopita'' and Easter ''tsoureki''.