In a small bowl, combine smoked paprika, mixed herbs, garlic powder, onion powder, salt, and black pepper.
Rinse the basmati rice several times until the water runs clear. Set aside.
Place the chicken thighs in a large bowl and coat them with the seasoning mixture, reserving about 1 teaspoon for later.
Heat olive oil in a large deep skillet or Dutch oven over medium-high heat.
Place the chicken skin-side down and sear for about 3 minutes per side until golden brown. Remove and set aside.
If necessary, remove excess oil, leaving about a tablespoon in the pan.
Add the chopped onion and sauté until soft and translucent.
Stir in the butter until melted.
Add the rinsed rice and toast for 1–2 minutes, stirring frequently.
Pour in the chicken stock and add the reserved seasoning. Stir well while scraping the bottom of the pan to release all the flavorful browned bits.
Taste the broth and adjust seasoning if needed.
Arrange the chicken thighs over the rice.
Cover tightly and cook over low-medium heat for 15–20 minutes, or until the rice is tender and all the liquid has been absorbed.
Remove from the heat and garnish with chopped green onions.
Cover and let the One Pot Chicken and Rice rest for 3 minutes before fluffing the rice with a fork and serving.