Preheat oven to 180 degrees C.
Mix olive oil, garlic, rosemary and thyme in a bowl.
Spread the mixture on the lamb.
Pour potatoes into a dish. Douse them in some olive oil, salt and pepper.
Place the lamb on the potatoes. Sprinkle some salt and pepper on the lamb.
Cook in the oven for 30 mins.
Turn the lamb and potatoes around and cook for another 30 mins.