Sumac grows in abundance throughout the Mediterranean, and its dried, ground berries are a fruity and astringent spice widely used in Middle Eastern cooking. If you can't find sumac, substitute 1/4 teaspoon grated lemon rind. You may need to add up to a tablespoon of water if the mixture is too thick to process smoothly. Serve with pita wedges.
This dip is SO easy to make, and it's just bursting with flavor. The tahini makes it - gives it richness and additional flavor. I added just a bit more olive oil (I used lemon flavored olive oil because there was lemon juice in the dip) because the mixture was too thick. And I didn't have sumac, but I had zahtar. It was just wonderful. Highly recommended. I served it with sangak bread, a fresh flatbread I'm able to buy at a Middle Eastern market. Otherwise, pita would work too.
