Add the flour, salt and turmeric into a larger glass or wooden bowl. Mix and make a well in the centre. Add the wet ingredients (sourdough starter, milk, yoghurt) and using your hands, incorporate the ingredients until all flour is well combined and there is no more dry flour visible.
The dough will be smooth and rather stiff. Cover the bowl with plastic and allow it to rest at room temperature until it has doubled in size.
Fermenting the Dough
In a 20°C/68°F kitchen, it will take approximately 8 hours for the sourdough to double in size. Warmer kitchens will take less time, colder kitchens will take longer. Seasons are great determinants- summer being a favourite.
In the summer you may start the process in the morning to be able to cook the naans in the evening or leave it in the fridge overnight if too hot.
Make and cook the sourdough naan
Place the dough onto your work surface and use a bench scraper to divide the dough into approximately 8 equal pieces. (approx 77g /2.71 oz each). Shape each piece into a ball and cover them with a kitchen towel. * see notes for storage or making later
While the dough is resting, preheat a cast-iron skillet over medium heat for 5-10 minutes. Feel free to oil the skillet if you wish, but I find this unnecessary. The naan will only stick initially but when cooked it will be really easy to turn on the other side.
Work with just one dough ball of dough at a time. Use a rolling pin to roll the dough into a round shape with a ⅛ inch thickness. Use a little flour if necessary to prevent sticking. The dough naan should be about 15-16 cm (6 inches) in diameter.
Place the rolled dough into the well-heated skillet and cook for 2-3 minutes. Flip the naan over and cook on the second side for another 1-2 minutes. Once cooked, remove the naan and place it on a wooden board or a ceramic plate. Repeat with the remaining dough. Serve hot or at room temperature.
Notes
When making the dough balls, please remember that this is when you can store these in a covered container, in the fridge for up to 3 days before cooking so can be made in advance and cooked freshly.