Put all the ingredients listed upto and including the flours in a large bowl (or food processor bowl). Make sure your yeast is active. Mix together. Add 1/2 cup water and as much more of it as required and knead the dough until it is soft, elastic but not sticky.
Shape it into a ball and place it in an oiled bowl, turning it to coat well with the oil. Cover loosely and let it rise till double in volume – about 1 1/2 hours. Knead lightly and let it rest in the same bowl for another hour or so till double in volume.
Then lightly flatten the dough and divide it into 6 or 8 pieces. 8 will give you smaller Ka’ak. On a lightly floured surface, roll out each piece of dough into an approximately 1/2" thick round. If using 6 pieces of dough roll out to about 7” in diameter. If using 8, then roll out to about 5” in diameter. Using a small round cookie cutter cut out a hole away from the centre towards the edge but not too close to it. Stretch it slightly (not too much or the dough will become too thin) to give it a more rustic look, if you would prefer. Place on a lined, floured or lightly greased baking sheet.
Repeat with remaining dough. You can bake the cut out rounds of dough as they are. Let the shaped dough rise till a bit puffy, for about 30 to 40 minutes. Brush the top with a mixture of milk and corn starch (or egg wash) and sprinkle generously with sesame seeds.
Preheat your oven to 220C (430F) with a baking stone or an inverted baking tray inside. Bake the breads for about 10 to 15 minutes till puffed and golden brown.
Let them cool a bit before digging in.
There was a suggestion that these breads would benefit from a bit of steam in your oven (ice cubes or boiling water in a heated pan) but I didn’t use it.