Heat the olive oil in a large skillet over medium-high heat.
Season the chicken thighs with salt and pepper, and brown them in the skillet until golden, about 5 minutes per side.
Remove the chicken and set aside. Add the chopped onion to the same skillet and cook until softened.
Stir in the paprika and flour, and cook for another 1-2 minutes.
Pour in the chicken broth, stirring constantly, and bring the mixture to a simmer.
Return the chicken to the skillet, cover, and simmer for about 25-30 minutes until the chicken is cooked through.
In a small bowl, mix the sour cream with a bit of the hot sauce from the skillet to temper it before adding it back in.
Add the sour cream mixture back to the skillet, stir to combine, and let it warm through.
Adjust the seasoning with salt, pepper, and optional lemon juice before serving.