In a large frying pan, melt the butter along with the oil, saute the onion and garlic until soft. Grind the herbs and spices, add to the onions.
Stir until fragant, add vinegar. Cook until it becomes a thick paste.
Take this paste and cover the chicken with it, marinate for at least 1 hour (better overnight).
When ready to cook, add the chicken to a large pan with enough water to make a paste. Cover and cook for 45 minutes.
Add the potatoes and cook until the potatoes are done.