Step 1 Preheat oven to 220ºC. Spray two baking trays with cooking oil. Fill the kitchen sink to one-quarter with warm water. Combine the water, yeast and sugar in a small bowl. Cover and place in the warm water in the sink for 5 minutes or until frothy.
Step 2 Sift flour and a pinch of salt in a large bowl. Make a well in the centre and pour in yeast mixture. Use a round-bladed knife in a cutting motion to form a soft dough. Turn out onto a lightly floured work surface. Knead until smooth. Cut into 4 equal portions. Place on prepared tray. Cover with a tea towel. Place in a warm area for 45 minutes to prove.
Step 3 Meanwhile, heat a large non-stick frying pan over medium-high heat. Spray onion with oil and add to pan. Cook, stirring, for 1 minute. Add mince and cook, stirring with a wooden spoon to break up any lumps, for about 5 minutes or until changed in colour. Add garlic, sumac and cumin and cook, stirring, for a further 5 minutes. Remove from heat. Stir in parsley. Set aside for 5 minutes to cool slightly.
Step 4 Roll each dough portion out until 1/2cm thick. Transfer to trays. Brush edges with water. Spread with tomato paste. Top half the pastry with mince. Fold pastry over to enclose and form a semi-circle. Pinch edges together to seal. Bake for 12-15 minutes or until golden. Serve with spinach or salad.