Preheat an oven-proof heavy-bottomed pan over med-low heat.
Preheat the oven to 200℃/Fan180℃.
Pat chicken legs dry with a paper towel and season with salt and freshly ground black pepper. Lightly drizzle with olive oil and rub all over lightly massaging the oil into the skin. Turn over and repeat for the other side.
Add the oil and butter to the hot pan then brown the chicken pieces on both sides, about 5-7 minutes per side. Transfer chicken to a plate and set aside.
While the chicken is browning thinly slice the onion and mince the garlic.
Add the onion slices to the pan and cook stirring frequently until soft and translucent about 5 minutes then stir in the minced garlic. Saute until tender, about 3-4 minutes.
Remove the pan from the heat and stir in the paprika and plain flour.
Mix well and cook until the floury taste has gone, about 4-5 minutes.
Stir in the chopped tomatoes and chicken stock and mix well.
Add the chicken and its juices back to the pan skin side up. Lightly spoon some of the tomato mixture over the chicken legs and place in the oven.
Cook in the oven for about 25-30 minutes until the chicken is cooked through and the sauce has slightly thickened.
Remove the pan from the oven and transfer the chicken to a plate.
Stir the sour cream into the sauce and stir gently until combined.
Garnish with parsley and serve right away with mashed potato, dumplings, rice or noodles.
Notes
If you prefer smaller chicken pieces just divide the legs into two pieces at the joint to get a thigh and drumstick.