Position the rack in the middle of your oven and then preheat to 450 degrees.
Scrub the carrots well but do NOT peel. Trim off the leafy green tops, leaving an inch or so. Cut the carrots in half lengthwise and place onto a rimmed, metal baking sheet.
Use metal tongs or a dark colored spatula to toss them in sunflower oil, turmeric, smoked paprika, oregano, garlic powder and kosher salt. Place the carrots cut-side facing down onto a rimmed metal baking sheet. If you're having trouble with them laying flat, I press them down with my fingers while sliding another baking sheet over top.
Roast in your preheated oven for 10 minutes then remove the top sheet pan (if using), rotating the pan with the carrots and roasting for an additional 10 to 15 minutes more.
Meanwhile, whisk together the garlic, tahini, lemon juice, olive oil and warm water until smooth. Season with 1/4 teaspoon both smoked paprika and kosher salt. (makes 1/2 cup)
Once the carrots are roasted, immediately transfer them to a platter. Drizzle a desired amount of the lemon tahini sauce over top and sprinkle with chopped pistachios and cilantro.
Serve immediately with the extra lemon-tahini dressing on the side.