Combine the marinade spices then, using your hands, rub them well into each piece of lamb.
Leave the meat to marinate at room temperature for about half an hour.
Heat a frying pan to medium high then add the oil. When it starts smoking, add the lamb and seal both sides of each of them. Reduce to medium and cook for 6 (rare) to 8 (well done) minutes basting regularly and turning half way through.
Place the lamb on a warm plate to rest. Add the stock to the pan and reduce for a couple of minutes using a wooden spoon to include the lovely cooked spicy bits from the bottom of the pan.