Tip the dough onto a floured surface and divide equally into 90g x 8 balls using a scale if you wish.
Knock back the dough pieces by rolling them in a circle motion on the work surface until they form tight balls.
Place the dough balls on a floured surface in an airtight container, make sure it is sealed. Leave a gap of 2cm between each ball.
At normal room temperature 19°C, the balls will take about 2 hours to prove. In a warm kitchen 23°C, an hour will be enough.
In the meantime make the filling. Steam the spinach in a saucepan with a few tablespoons of water until it’s wilted. Run under cold water, then squeeze out the excess liquid. Chop, then place in a bowl. add the sliced leek. Now chop the wild garlic and add to the bowl with the sumac. Season with salt and pepper.
Rub a large cast iron pan using kitchen paper with a little olive oil and place on the hob to heat.
Sprinkle a little flour on your hands and on the work surface. Open a dough ball by flattening and stretching the dough gently with your fingers.
Pick the dough up and gently, without tearing, stretch it a little further over your fists. Repeat with the remaining dough balls. Transfer one shaped flatbread onto a peel or baking sheet, dusted with cornmeal to prevent sticking. Add the filling and 4-5 torn pieces of mozzarella and grated Parmesan, place a prepared dough disc on the top. Press to seal and dust with a little more sumac. Transfer the filled dough to the hot pan. Repeat with the remaining dough balls.
Once it starts to bubble and turns golden underneath, turn and then place in the oven for 3-4 minutes to finish cooking. Eat immediately or wrap in foil and reheat when required,