Mix flour, paprika, sea salt, and black pepper in a shallow dish. Dredge the chicken thighs and legs in the flour mixture, thoroughly coating each piece. Set aside any leftover flour.

Heat vegetable oil in a large Dutch oven over medium-high heat. Add coated chicken pieces, browning for about 3 minutes on each side until golden. Remove and set aside.

In the same pot, sauté chopped sweet onion over medium heat for 2-3 minutes until translucent. Add cayenne pepper and remaining paprika, stirring to release aroma.

Return browned chicken to the pot, pour in chicken stock, and stir. Bring to a gentle boil, cover, and simmer for 45 minutes.

Mix reserved flour with sour cream in a bowl, whisking until smooth. Gradually add cooking liquid to temper. Stir sour cream mixture into the pot and simmer uncovered for 5 minutes.

Taste and adjust seasoning if necessary; the Chicken Paprikash is now ready to be served.