Heat vegetable oil in a large skillet over medium heat. Add chicken thighs and cook until browned on both sides, about 5 minutes per side. Remove and set aside.
In the same skillet, add chopped onions and cook until soft and translucent, about 4 minutes.
Stir in the sweet paprika and flour, cooking for 1 minute until fragrant.
Slowly whisk in the chicken broth, scraping any browned bits from the pan. Bring to a simmer.
Return the chicken thighs to the skillet, cover, and cook for 25 minutes or until chicken is cooked through.
Remove skillet from heat and stir in sour cream until smooth. Adjust salt and pepper to taste.
Serve hot over egg noodles or rice.
Notes
For best results, use fresh Hungarian paprika and freshly ground black pepper. Leftovers store well for 2 days refrigerated.