Season the chicken thighs with salt and black pepper.
Heat the oil or lard in a large heavy-bottomed pot over medium-high heat. Brown the chicken on both sides, working in batches if necessary. Remove and set aside.
Reduce the heat to medium. Add the chopped onions and cook for 6–8 minutes, until soft and lightly golden.
Add the garlic and cook for another minute.
Remove the pot from the heat and stir in the sweet and hot paprika. Add the tomato and bell pepper.
Return the pot to the heat and pour in the chicken broth. Stir well, scraping up any flavorful bits from the bottom.
Return the chicken to the pot. Cover and simmer gently for 35–45 minutes, until the chicken is tender and cooked through.
In a bowl, whisk together the sour cream and flour until smooth.
Slowly whisk a little of the hot cooking liquid into the sour cream mixture to temper it.
Stir the sour cream mixture into the pot and simmer gently for 5–8 minutes, until the sauce thickens. Do not let it boil vigorously.
Taste and adjust the salt and pepper.
Serve hot over nokedli, egg noodles, or dumplings, with an extra spoonful of sour cream and fresh parsley if desired.
