Mahleb or Mahlab is an aromatic spice made from the seeds of a species of cherry, Prunus mahaleb (the Mahaleb or St Lucie cherry). The cherry stones are cracked to extract the seed kernel, which is about 5 mm diameter, soft and chewy on extraction. The seed kernel is ground to a powder before use. Its flavour is similar to a combination of bitter almond and cherry, and similar also to marzipan.
It has been used for centuries in the Middle East and the surrounding areas as a flavoring for baked goods. Recipes calling for the fruit or seed of the “ḫalub” date back to ancient Sumer. In recent decades, it has been slowly entering mainstream cookbooks in English.
In Greek American cooking, it is the characteristic flavoring of Christmas cake and pastry recipes. In Greece, it is called μαχλέπι (mahlepi), and is used in egg-rich yeast cakes and cookies such as New Year vasilopita and Easter tsoureki breads (known as cheoreg in Armenian and çörek in Turkish).
In Turkey, it is used in poğaça scones and other pastries. In the Arabic Middle East, it is used in ma'amoul scones. In Egypt, powdered mahlab is made into a paste with honey, sesame seeds and nuts, eaten as a dessert or a snack with bread.
In English, mahlab is sometimes spelled mahalab, mahlep, mahaleb, etc.