01 In a large bowl, stir together the cumin, coriander, paprika, cinnamon, 1½ teaspoons salt and 2 teaspoons black pepper. Measure 1 teaspoon of the mix into a medium bowl; set aside. Into the remaining spice mix, whisk ⅓ cup oil, 1 tablespoon of tahini and 2 tablespoons of lemon juice. Add the chicken and onion, then toss to combine. Let stand at room temperature while the broiler heats.

02 Heat the broiler with a rack about 6 inches from the element. Line a rimmed baking sheet with foil, then mist with cooking spray. Meanwhile, to the reserved spice mix, add the yogurt, the remaining 1 tablespoon olive oil, the remaining 2 tablespoons tahini, the lemon zest, the remaining 1 tablespoon lemon juice and 2 tablespoons of mint. Taste and season with salt and black pepper. Stir, then set aside until ready to serve.

03 Transfer the chicken-onion mixture, along with its marinade, to the prepared baking sheet, then distribute in an even layer. Broil until the chicken is lightly charred on both sides, 18 to 20 minutes, flipping the pieces once about halfway through. Remove from the oven, sprinkle with the remaining mint and toss to combine. Transfer the chicken to a serving platter and serve with the yogurt-tahini sauce.