Combine flour, salt, pepper, paprika, and garlic powder in a shallow dish. Reserve 2 tablespoons of this seasoned flour for the gravy.
Dredge chicken thighs in the seasoned flour mixture, shaking off excess.
Heat oil in a heavy-bottomed skillet or Dutch oven over medium-high heat. Sear chicken skin-side down for 6-8 minutes until golden and crisp. Flip and sear for 3 minutes. Remove chicken from the pan and set aside.
Add sliced onions, bell pepper, and celery to the remaining fat in the pan. Sauté for 5-7 minutes until the onions are translucent and slightly caramelized.
Stir in the minced garlic and cook for 60 seconds until fragrant.
Sprinkle the reserved 2 tablespoons of seasoned flour over the vegetables. Stir constantly for 2 minutes to create a light roux.
Gradually whisk in the chicken broth, scraping the bottom of the pan to deglaze the brown bits (fond). Bring the liquid to a simmer.
Place the chicken thighs back into the pan, skin-side up. Reduce heat to low, cover with a lid, and simmer for 25-30 minutes until the chicken reaches an internal temperature of 165°F.
Remove from height and stir in the heavy cream to enrich the gravy. Adjust seasoning with additional salt and pepper if necessary.
Serve the chicken and plenty of gravy over portions of warm cooked white rice.