In a blender, combine the sour cream, egg, baking powder, and vanilla extract. Blend well.

Melt the butter.

In a large bowl, mix the flour with the salt, ground mastic, ground mahlab, toasted sesame seeds, and toasted black sesame paste.

Add the corn oil and melted butter to the flour mixture. Rub together with your hands until combined.

Add the blended mixture of sour cream, egg, baking powder, and vanilla extract to the flour mixture.

Knead until all the ingredients come together into a smooth dough.

Let the dough rest for 1 hour.

Cut the dough and dates, then start shaping the cookies.