Use only recently purchased flour because flour that has been stored for a long time will go slightly bitter. Put the flour into a mixing bowl and adding a little water at a time, knead a medium strength dough. Cover this with a lid or kitchen towel to prevent drying out and let this sit for about 10 minutes. If you do not do this then the edges of the puris will crack when you roll them out.
Break off a small lump of dough and roll it between your palms to form a sphere, roughly 3 cm in diameter. Try to form a perfect ball because imperfections will affect the shape and inflation of the puris when you fry them. Make several balls of the same size and place them near the surface where you will roll out the puris. Take a few tablespoons of the oil in a bowl to use for rolling (will explain how). Put the rest of the oil in the kadhai or wok and heat on a high heat.
Start rolling out the puris by dipping one side of the ball in the bowl of oil so that you have about a quarter of a teaspoon on it. The reason for doing this rather than rolling them with the help of flour is that the flour burns when you are frying the puris. You will find that it is a little difficult to roll out the puris with oil on them but you will get the hang of it. Roll them out evenly to form a round of about 10 cm and 2 mm thick. It is important to roll them out evenly because they will not inflate while frying if they are uneven and this will affect the cooking and the taste.
Test whether the oil is hot enough to start frying by dropping a tiny ball of dough into it. if it sizzles and rises to the surface immediately, the oil is hot. Now pick up the rolled out puri and gently slide it into the hot oil. DO NOT DROP IT FROM A HEIGHT BECAUSE HOT OIL WILL SPLASH ON YOU. The puri will start to sizzle immediately and will start to inflate after a couple of seconds. Turn it over on the other side and cook for a further 3-4 seconds until it goes a nice golden colour. A golden colour means that the puri is well cooked. Ideally, you would be rolling out the next puri while you are frying the first one but if this seems too complicated, you can roll a few out before you fry them or ask someone to help you with the frying. Remove from the oil and place on a paper towel to absorb any oil. The puris are ready to eat.