Mix together the dry ingredients for the flatbread then add the yogurt and oil. Add the milk, a little at a time, and mix until a rough dough starts to form. You might not need all the milk.
Turn the dough out onto a floured surface and knead until it just comes together in a smooth ball. Cover in plastic wrap and allow to rest at room temperature for 30 minutes.
roll tennis-sized balls of dough out onto a floured surface (to around ½cm thick) and cook in a hot pan until golden and bubbling then flip and cook for another minute or two on the other side.
Remove from the pan, brush with melted butter (optional) and keep wrapped in foil until ready to serve.
To re-heat the flatbread keep wrapped in foil and heat in the oven for 10-15 minutes until heated through.