Season chicken thighs with salt and pepper. In a pot, melt 1 tablespoon of butter over medium-high heat and brown the chicken skin-side down for 3-4 minutes. Remove and set aside.

Melt the remaining butter, then sauté onions until soft. Add red pepper, garlic, tomato paste, paprika, salt, and pepper, stirring for 2-3 minutes until fragrant.

Pour in chicken stock and reduce heat to medium. Return chicken to the pot, skin-side down, and simmer for 20-25 minutes. Use a thermometer to ensure chicken reaches an internal temperature of 165°F.

Mix flour with sour cream, then temper with ½ cup of cooking liquid. Add back to the pot, stirring to avoid clumps.

Return chicken to the pot, coating it with the sauce. Garnish with parsley and serve with your choice of side.