Season the chicken thighs generously with salt and pepper. Heat a large, deep skillet or Dutch oven over medium-high heat and add the olive oil.
Place the chicken skin-side down and sear until the skin is golden and crisp, about 4–5 minutes. Flip and sear the other side for 2–3 minutes. Remove the chicken and set aside.
In the same pot, lower the heat to medium. Add the onion and a pinch of salt. Cook, stirring occasionally, until softened and translucent, about 4–5 minutes.
Add the garlic and cook for another 30 seconds until fragrant. Stir in the rice and let it toast for 1–2 minutes so it looks slightly glossy.
Pour in the tomatoes and chicken broth. Stir in cumin, paprika, oregano, and red pepper flakes if using. Bring to a gentle simmer.
Nestle the browned chicken back into the pot, skin side up. Scatter the chickpeas and olives over the top. Add lemon zest and juice, then bring back to a simmer.
Cover, reduce heat to low, and cook for 18–22 minutes, until the rice is tender and the chicken is cooked through. Avoid lifting the lid too often.
Remove from heat and let rest, covered, for 5 minutes. Fluff the rice with a fork, adjust seasoning with salt and pepper, and sprinkle with chopped parsley.
Serve warm, with extra lemon wedges on the side if you like a brighter finish.