Pat the chicken thighs dry with paper towels. Season generously on both sides with Cajun seasoning, paprika, garlic powder, onion powder, thyme, salt, and pepper.

Heat a large cast iron skillet over medium-high heat and add the olive oil. Once hot, place the chicken thighs skin-side down and sear until the skin is golden brown and crispy (about 4–5 minutes per side). Remove the chicken from the skillet and set aside.

In the same skillet, melt the butter, then add the onions and bell peppers. Sauté for 5–6 minutes, stirring often, until soft and lightly caramelized. Add the minced garlic and cook for another 30 seconds. Sprinkle in 1 tablespoon of flour, stirring well to coat the veggies.

Gradually pour in the chicken broth, whisking as you go to remove any lumps. Bring it to a simmer — the sauce will start to thicken into a silky gravy. Add the heavy cream (if using) and adjust seasoning.

Return the seared chicken thighs to the skillet, nestling them into the gravy with the peppers and onions. Spoon some gravy over the top and cover the pan. Simmer on low heat for 15–20 minutes.

Spoon a bed of steamed white rice into a bowl. Place the smothered chicken on top and ladle plenty of that rich onion-pepper gravy over it.