To make the dough, mix the yeast and 1/4 cup of warm water and 1/2 cup of flour. Set aside until the mixture becomes foamy, about 10-15 minutes.
Now add four more cups of flour, salt, olive oil, and the remaining 1 cup of warm water.
Knead into a soft but smooth dough. Add more flour if necessary.
Cover and allow the dough to rest for at least 2 hours or even overnight, in a refrigerator.
To make the filling, heat the olive oil in a skillet. Now add the onions and stir quickly over high heat until lightly browned but still crunchy. Add the cumin, coriander, chilli powders and black pepper as well as salt to taste.
Stir in the coriander leaves and set aside to cool.
Punch down the risen dough and divide into six equal-sized pieces. Roll each piece into a smooth ball. Set the dough balls aside to rest for 10 minutes, covered.
Roll out two of the dough balls into 8-inch discs, using a little flour if necessary.
On one disc, spread out a third of the onion mixture evenly.
Moisten the edges of the second disc by brushing on a smidgen of water, then press down on top of the other disc with the filling. Press the edges together to seal.
Roll out the pizza into a 12-inch round. Make two more pizzas the same way using the remaining dough balls.
Preheat the oven to 400 degrees.
Place the pizza on a lightly oiled baking sheet. Bake each pizza in the oven, one or two at a time, for 22-23 minutes or until lightly golden and crisp.
Brush the top with olive oil as soon as it comes out of the oven.