Step 1Remove the tops from the carrots, pick off all the leaves, then wash and dry the leaves thoroughly (you should have about 3 to 3 1/2 cups). Place all the leaves on your cutting board and finely chop (you should have about 1 1/2 cups). Place 1 cup of the finely chopped carrot top leaves into a bowl and discard or reserve the rest for another use. Stir the sesame seeds, sea salt and sumac into the carrot top leaves in the bowl and reserve the za’atar until ready to use. You can make the za’atar up to 3 days in advance and store in the refrigerator.
Step 2In another bowl, whisk together the labneh, tahini and 2 tablespoons olive oil. Using a microplane grater, grate the garlic into the labneh mixture and stir until evenly mixed. Season the labneh sauce with salt and pepper.
Step 3Prepare a charcoal grill for direct, high heat grilling or heat a gas grill to high. (Alternatively, heat a cast-iron grill pan over high heat.) Scrub the carrots clean and dry thoroughly, then place in a bowl. Add the remaining 2 tablespoons olive oil, season with salt and pepper, and toss to coat the carrots with the oil.
Step 4Place the carrots on the grill and cook, turning as they char lightly, until soft and blackened nicely in spots, about 20 minutes.
Step 5While the carrots cook, spread the labneh sauce over the bottom of a large serving platter. Transfer the cooked carrots directly from the grill to the platter, piling them up in the center. Sprinkle the carrots with some of the za’atar (you won’t use it all) and drizzle with more olive oil to serve.