Put the flour in a bowl. Gradually add enough water to make a soft dough (about 7 fl oz of water).
Knead the dough for several minutes until smooth. Cover the dough with a damp cloth and set aside for half an hour to rest. If the dough is runny, flour your hands and knead for a few more minutes.
Form ten equal balls and dust each with flour. Heat up a cast-iron griddle or frying pan over a low flame on a medium heat.
Take one of the balls of dough, flatten it between the palms of the hands, and dust it with flour on both sides.
Roll out to a 5 1/2" round, and slap the roti onto the heated. surface. Cook for about a minute, or until soft bubbles begin to form, then turn over and cook for half a minute on the second side. If you have a gas cooker, then use tongs to hold the roti in a second flame for 3 seconds on each side. The roti should puff up.
Alternatively if you have an electric stove, put the roti under a hot grill for a few seconds until it puffs up.