Mahleb or Mahalepi is an aromatic spice made from the seeds of a species of cherry, “Prunus mahaleb” (the Mahaleb or St Lucie cherry).
On this species of cherry, we use at the same time wood, bark, leaves, fruit, roots, resin, fruit and of course what we are talking about, the seed (the mahaleb). The name of St Lucia wood comes from the monastery of the Meuse "St. Lucia-de-Mont"; this wood was very used for the manufacture of objects of worship.
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 flavor 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.
Mahleb is used in small quantities to sharpen sweet foods and cakes, and is used in production of tresse cheese.
You can find Mahleb in pastries and breads from Greece to Iraq
But it's a shame to use it only in the sweet recipes, try the spice in the salty recipes!
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.