Prepare the Chicken:
Season the chicken thighs with salt and pepper. Heat the vegetable oil in a large saucepan over medium heat. Brown the chicken thighs in batches for 5–8 minutes until golden all over. Remove from the pan and set aside.

Cook the Vegetables:
In the same pan, add the chopped onions and cook for 8–10 minutes until softened and golden. Add the chopped bell peppers and cook for an additional 3 minutes. Stir in the minced garlic and chopped tomatoes, cooking for 5–8 minutes until the tomatoes begin to break down.

Add Paprika and Flour:
Sprinkle in the flour, sweet smoked paprika, and hot paprika (if using). Cook for 30 seconds to release the flavors.

Simmer the Chicken:
Return the browned chicken thighs to the pan, mixing gently to coat with the paprika mixture. Pour in the chicken stock, bring to a boil, then reduce the heat and simmer, covered, for 15 minutes. Remove the lid and continue to simmer for another 15 minutes until the sauce has thickened.

Finish the Sauce:
Stir in the sour cream and cook for 5 more minutes, ensuring the sauce is creamy and well combined. Adjust seasoning with salt and pepper as needed.

Serve:
Serve the chicken paprikash hot over boiled potatoes, egg noodles, or rice.