Mix together all-purpose flour, paprika, sea salt, and black pepper in a shallow dish. Dredge each piece of skin-on, bone-in chicken, ensuring it's evenly coated, and set aside the leftover flour mixture for later use.

In a large Dutch oven, heat about two tablespoons of vegetable oil over medium-high heat. Add seasoned chicken pieces and brown for approximately 3 minutes on each side.

In the same pot, add chopped sweet onion and sauté for 2 minutes until tender. Sprinkle in the remaining paprika and cayenne pepper if desired.

Return the browned chicken to the pot, pour in chicken stock, bring to a gentle boil, reduce heat to low, cover, and simmer for about 45 minutes.

Combine reserved flour with sour cream in a bowl. Gradually stir in hot liquid from the pot to temper the sour cream. Blend this mixture back into the pot, stirring well.

Taste and adjust seasoning, removing the pot from heat to rest briefly before serving.