This is the basic Bengali fried bread, but with significant modifications to the process using a few modern tools unavailable to grandmothers so that you no longer need years of practice to get everything right.
In a large mixing bowl, put the flour. make a small whole in the middle, put the ghee and the salt. Mix the flour and ghee by hand for a minute or so till the ghee is fully incorporated.
Add the water a little at a time, kneading the flour till a firm, smooth, pliant dough is obtained.
Let the dough sit for 30 minutes.
On a greased countertop, use a rolling pin to roll the dough into an even sheet about 1/4" thick, or as thin as you can handle successfully - too thin, and all kinds of things will go wrong and unlike popular belief, thin is not necessarily a pre-requisite to puffing. Use a pasta roller, if you have one.
Use a 3-4" round cookie cutter to cut out as many discs of dough as possible. Knead up the remaining dough and repeat. Fancy shapes are also possible - they will all puff.
In an 8" wok or round-bottom pan, put at least 3-4" of some kind of light oil (canola or sunflower). For those less concerned with calories, you can use a mixture of ghee or even all ghee.
When the oil is just below smoking hot, put the discs in one at a time and use a metal slotted spoon to push down very lightly and immerse the dough in the oil. It should start puffing in seconds. The main trick to puffing is to make sure that the luchi is still substantially immersed in the hot oil when the puffing completes.
If your puris are not puffing well, make sure that there's enough oil to substantially immerse the puris in while they're puffing, and also that the oil is hot enough.
When fully puffed, turn it over, lightly brown the other side for a few seconds and take out onto a kitchen towel or in a large colander to drain the excess oil.