Put the flour into a large bowl. Add the salt (1 tsp) on one side of the bowl and yeast (1 tsp) on the other side. Add the nigella seeds (1 tbsp).
Put the rapeseed oil (2 tbsp), natural yogurt (3 tbsp) and milk (120ml) into a jug. Mix together the dry ingredients and add about ¾ of the wet ingredients. Mix everything together. You want to get a rough dough where there are no loose bits of flour but the dough isn't too sticky. Add some more of the remaining wet ingredients if needed to help bring everything together.
Knead the dough until it's smooth and stretchy (about 8 minutes in a mixer with a dough hook on a low speed or 10-15 minutes by hand).
Put the dough into a bowl and cover with clingfilm. Leave to prove until it has doubled in size (this will take about 1½ hours - the size is more important than the time).
Once the dough has proved knock the air out (by kneading it a couple of times) and split it into 8. Roll out each ball into an oval (pitta bread) shape about 5mm thick and place into a baking tray. If you find the dough a bit sticky, sprinkle over a little extra flour to make it easier to work with. Cover the tray(s) loosely with cling film and leave to prove for 15 minutes.
While the dough is proving, pre-heat your oven to 240ºC/220ºC fan.
Remove the cling film and bake the breads for about 5-6 minutes. You're best going a bit "bake-off" with these and watch them through the oven door. Once they've puffed up leave them for another minute and them remove them from the oven.
Serve warm or cold.