Make the filling first. Boil the potatoes with a bit of salt until theyu2019re done and soft. Put them in a largish bowl and aad the salt, oil, black pepper and coriander powders. Mash the potatoes really well, so no lumps remain.
Add the chopped coriander and the spring onions and mix well. Keep aside.
Now make the dough. Do this by hand or machine. Put the flour salt and oil in the processor bowl. Slowly add 1 cup of water and knead until you have a smooth and elastic dough, adding as much more of water as required.
Shape the dough into a ball and place in an oiled bowl, cover with a cloth and let it rest for about an hour.
Now make the Bolani. Divide the dough into 8 equal portions. Work with one portion at a time, keeping the others covered so they do not dry out. Take one portion and roll into a smooth ball. Flour your working surface lightly and roll out the ball of dough into a round (like a tortilla) of about 10u201d to 12u201d in diameter. A thinner round of dough is desirable.
Dvide your filling into 8 portions and place one portion of the filling on one half of the round (forming a semi-circle of filling) leaving about 1/4u201d at the edge for sealing. Fold the dough over the filling to form a half-moon shape and press the edges with your fingers, to seal well. I used the tines of a fork to make the edges look pretty but this is not usual.
Repeat this with the rest of the dough and filling to make 8 Bolani. Pour about 1/8ththe oil in a shallow frying pan. When it is hot enough place one Bolani in it. The oil around the Bolani should sizzle. Turn the heat down to medium, and cook the Bolani on both sides by pressing down with a spatula on and off so that it flattens a little more.
When done (should take about a couple of minutes), the Bolani should a golden brown on both sides. Let the Bolani drain on paper towels.
Add more oil when necessary and repeat this with the other 7. Serve slightly warm or at room temperature with the Chatni Gazneesh and some Mint Chakkah (the recipes follow).