Preheat oven to 450°F. Meanwhile, in small bowl mix 2 tablespoon brown sugar, 2 teaspoon Kosher salt, 1 teaspoon cumin, 1 teaspoon paprika, 1 teaspoon chili flakes, ¼ teaspoon cinnamon, ¼ teaspoon clove. Thinly slice 1 red onion.
Transfer 2lbs chicken thighs to a large sheet pan and cover generously with olive oil (about 2 tbsp). Sprinkle over the spice blend and toss to coat. Push the chicken to one side, then add 300g cherry tomatoes and sliced red onion to the other. Cover with a bit more olive oil and a pinch of salt then toss to coat and arrange everything so vegetables are on the bottom and chicken is on top.
Transfer to the oven and bake for 20 minutes. Move the rack to the upper third, turn the oven to broil and continue cooking until golden brown and slightly charred, rotating the pan half way, about 5-10 minutes.
While the chicken cooks, add 1 cup Greek yogurt and the juice of one lemon to a small bowl. Grate in 1 clove of garlic and season with ½ teaspoon salt and lots of cracked black pepper. Mix, then taste and adjust seasoning. In this time you can also prep your toppings: warm some pittas or cook rice, chop parsley and peppers, and crumble feta.
When the chicken is ready, let rest for 5 minutes to absorb juices, then slice and serve on pitas or rice with the cooked vegetables and all your toppings.
