Toast the cinnamon sticks, black peppercorns, cumin and coriander seeds in a sauté pan. Remove from the heat and add to a spice or coffee grinder to create a powder. Set aside and allow to cool.
In a small bowl, add the sumac, paprika, allspice, cardamom, clove, and nutmeg. Whisk in the ground, toasted spices and transfer to a glass container with a tight fitting lid.
Store in your spice cabinet and it will last about 3 months, after that the potency diminishes. Makes about 3/4 cup.