Directions

• Cut the bread into 1/2-inch pieces and toss it with the buttermilk in a large bowl until each piece is moistened.  Add the lamb, onion, salt, spices, and baking soda; chop 1/2 cup parsley leaves, and add them as well.  Sift the powdered milk evenly over the mixture, and combine it all with your hands, a potato masher, or a spatula, mixing it thoroughly but taking care not to manhandle it.
• Scoop the mixture into 1/2-cup mounds and shape it into logs that are 4 or 5 inches long (you’ll have 8 – 10 kebabs).  Place them on a plate, cover loosely in plastic, and refrigerate for at least 30 minutes;  this gives the fat in the lamb a chance to firm up before it cooks, so it keeps its integrity.
• If you’re grilling the kebabs, heat the grill until the fire has burned out but the coals are white-hot.  (The fire needs to die down before you cook, or else the fat from the kebabs could melt and make it flare up).  Place each kebab directly on the grill, and cook for 3 – 4 minutes, until they’re deeply golden with a nice crust, then turn and cook for another 2 – 3 minutes.  Cut into one; it should be cooked through but still very juicy.
• If you’re not grilling the kebabs, heat your oven to 400°F, and add the canola oil to a large ovenproof skillet over high heat.  Put the flour in a wide, shallow bowl, and set it aside.  Test the oil by dropping a pinch of flour into the pan; you’re ready to cook when it sizzles right away but doesn’t immediately turn brown.  
• Lightly dredge the kebabs in flour, one at a time, so all sides are coated, patting them gently between your hands to reshape them and shake off any excess flour. Lay them side by side in the pan and decrease the heat to medium.  Cook these in batches if you need to; it’s important that the pan doesn’t get over crowded.
• Let the kebabs cook, undisturbed, for 5 – 6 minutes, or until the bottoms are a deep golden-brown.  Flop them, and immediately transfer the skillet to the oven. Bake for 7 – 8 minutes, until they’re no longer pink in the middle.
• Move the kebabs to a serving platter, and drizzle the tahini sauce and olive oil them.  Chop the cilantro and remaining 2 tablespoons parsley, and scatter them over the tops.
• Prepared Tahini:
• Combine the lemon juice and garlic in a nonreactive bowl; set it aside for 30 minutes to steep.
• Meanwhile, whip the tahini with a stand mixer or an electric mixer on high speed for about 10 minutes, until its glossy and light, like cake batter.  It’s nearly impossible to over whip it, so feel free to spend a little time here.
• Strain the lemon juice.  Decrease the mixer’s speed to medium, and add the juice and salt; the tahini will seize up at first, but don’t freak out!  Keep whipping it at medium speed and it will be incorporated.
• When the tahini has a uniformly tacky, almost a fudge consistency, add the ice water, about 1/4 cup at a time, and increase the speed to high.  At first, the sauce may seize up again and look almost curdled, but keep adding the ice water, whipping well after each addition.  It will smooth itself out and should look like a thick mousse.  Every tahini is different; if, after you’ve added all the water and it’s still too thick, keep adding water by the tablespoon until it lightens up.
• Prepared tahini will stay good for about 2 days in the fridge.  If you’re making it in advance, let it warm up just slightly on the counter, and whip in 1 – 2 tablespoons ice water to restore some of its lightness.