Sumac roasted potato wedges

For the last couple years there has been an increased interest in the food of the Israel, Turkey, Libya and Tunisia and the near middle east, personally I think  this is  mainly due to works of  Yotam Ottolenghi. He has brought a new flavour palate to the UK, so much so that sumac and z'atar now  routinely appear on most supermarket shelves. We enjoy sumac sprinkled on oven baked potato wedges which have been tossed on little olive oil and roasted for about 40 minutes until soft and golden, delicious served with a garlic yoghurt dip or as a side dish.