In the bowl of a standing mixer whisk together the flour, salt, and fennel seed. Attach the dough hook, and slowly add the water up to 1 1/4 cups. Knead for 10 minutes, using the dough hook, until you get a smooth and sticky dough, adding more water as needed. It should be a very wet, stretchy dough so you can stretch it in the next step, but it should be dry enough to form a definable dough mound.
Divide the dough into 4 balls, place in a large bowl, and drizzle generously with olive oil. Cover and rest the dough on the countertop for one hour. This resting period is crucial to the stretching process. Without resting the dough, it will contract too much each time you try to stretch it, and it would be very difficult to get it as thin as needed.
Prepare the filling by heating up the olive oil in a heavy bottomed pot over medium-high heat. Add the onions and spices. Reduce the heat to medium-low, cover the pot, and lightly simmer for 15 minutes, or until the onions are limp and translucent. Drain the onions, and reserve the oil for another purpose. If you are working with a dark, hard surface, you can use it in the next step. I was working with white marble as my work surface and didn't want to risk the turmeric staining it.
On a clean surface, drizzle a little oil and smear it with your hands. Place one of the dough balls on it and begin to flatten it with with palm of your hand and fingers. Next, start to spread it out into a circle. Soon you'll be able to lift up each side and gently stretch it from the middle. Work all around the circle of dough. Lastly, focus on stretching out the edges. Thanks to the oil, it shouldn't stick to your work surface. The result is a very thin circle of dough.
Spread a little of the filling all over the surface of the dough with your hands. Imagine that you're folding a business letter to fit into a business envelope. Fold the dough over from the right towards the left with the dough only covering the middle third of the circle. Spread a little more filling on the dough. Fold the other third over the center. Spread a little more filling on the dough. Now fold the lower third of the long, narrow strip of folded dough up over the middle third, followed by a little more filling. Finally, fold the top third over the middle to form a neat packet of layers of dough.
Put aside and stretch a second dough ball into a thin circle, and spread with filling, just like the first one. Place the packet of layered dough smack in the middle of the circle, and repeat the folding technique you followed for the first one. You'll end up with a packet of dough with double the layers of the first packet. You can continue this process to add additional layers up to 7 layers, but I stopped with 2 balls of dough per loaf.
Repeat with the 2 remaining balls of dough to form a second loaf.
Preheat the oven to 400˚ F, and drizzle a little olive oil onto the bottoms of 2 separate oven-safe pans. Place a finished layered loaf into each pan and rest for 30 minutes. Gently spread each loaf with your fingers to make it flatter and larger.
Bake on the center rack for 40 minutes. I recommend checking it at 30 minutes, but mine took 40 full minutes to get a browned, crispy top. The inner layers were perfect.
I served it with a dollop of yogurt on it, and Sawsan recommends a salad, which is a perfect complement.