Heat the butter in a small heavy-bottomed frying pan over a medium heat. Fry the onions with a pinch of salt, stirring often, until very soft and golden brown. Season with chilli powder and set aside to cool. 

Put the flour in a large bowl with ¼ teaspoon of salt and make a well in the centre. Squeeze the onions with the back of a spoon and add any butter that comes out to the flour. Start trickling the warm water into the well while you mix with your other hand. Bring the dough together and knead for a good couple of minutes. You want dough that is soft and pliable – if it is too dry, add a splash of water or if it is too sticky add a little more flour. 

Divide the dough into four pieces. Roll out each piece thinly on a floured surface and spread a quarter of the onion over the surface. Roll up into a tube, pinch the ends and form the tube into a coil with the outside end tucked underneath. It should resemble a cinnamon roll. Finally roll it flat again into cardboard-thin rounds. Repeat with the remaining dough. The rounds will contract as they sit so you’ll need to pull them out a little flatter with your hands as you take them to the pan. 

Heat a frying pan over a medium-high heat and use kitchen paper to rub it with a little oil. Fry the breads for about 2 minutes on each side, turning after each minute. They should puff up a little and begin to blister as they cook. Serve hot from the pan.