Pat the chicken thighs dry with paper towels and season generously with salt, pepper, and half of the smoked paprika. Heat olive oil in a large skillet or Dutch oven over medium-high heat. Sear the chicken skin-side down until golden brown, about 5 minutes per side. This locks in the juices and adds incredible flavor to the rice later.
Remove the chicken and set it aside. In the same pan, add chopped onion and bell peppers, cooking until softened, about 5 minutes. Stir in garlic and cook for another minute until fragrant. This builds the flavor base for the whole dish.
Add the rice directly into the pan with the vegetables, stirring to coat it in the oil. Sprinkle in the rest of the smoked paprika, cumin, oregano, and chili flakes if using. Toast the rice for about 2 minutes, letting it absorb all the spices. This little step gives the rice a nutty, aromatic quality.
Pour in the diced tomatoes with their juices and chicken broth, stirring everything together. Return the chicken thighs to the pot, nestling them gently into the rice mixture. Bring to a boil, then reduce the heat to low, cover, and let it simmer.
Allow the rice and chicken to cook together for about 25 minutes, or until the rice is tender and the chicken is fully cooked through. Check occasionally to make sure the rice is not sticking, and give a gentle stir if needed. The juices from the chicken will infuse into the rice, making it extra flavorful.
Once the rice is cooked, stir in the frozen peas and let them warm through for 2–3 minutes. Sprinkle chopped parsley over the top and serve with lemon wedges. The lemon juice brightens the entire dish and balances the spices beautifully.