For many of us, something red on our plate signals to our palates either sweetness (as with strawberries or raspberries) or spiciness (usually chillies). But sumac has neither of those flavours: it's tart. Its sourness is different to that of lemon, which some recipes say can be used as a substitute: sumac is more astringent and tannic.
The spice comes from the dark reddish-purple sumac berry, which is dried and then ground to a coarse, gritty powder, and that is usually how it's sold commercially. The spice should be stored in an airtight jar, in a cool, dark place. Sumac is often one of the ingredients in spice blends such as za'atar.
It is also a versatile spice and complements meats, fish, vegetables, legumes and dairy products. And it often appears in Middle Eastern mezze spreads, sprinkled over salads, hummus and yogurt.
For kebabs, mix ground lamb (or a mixture of beef and lamb) with minced garlic, onion, parsley, ground cumin and other spices. Shape the mixture into meatballs then skewer them.
Grill the meat until crusty outside and moist within then sprinkle ground sumac over it. Remove the mixture from the skewers and wrap in soft flat bread, adding chopped fresh tomatoes, herbs and grilled peppers and onions.
For a quick and easy salad, cut tomatoes and cucumbers into chunks and add smaller pieces of red onion. Mix with salt, extra-virgin olive oil and a sprinkling of sumac, and serve with grilled lamb, beef or chicken.