Place the lamb fillets flat in a dish, sprinkle with the oil, rosemary leaves and plenty of pepper, and turn the lamb to coat.

Cover and refrigerate for 4 hours or overnight if possible.

Remove from the fridge at least 30 minutes before cooking

Immediately before cooking, season the lamb with salt.

Heat a heavy-based frying pan until very hot and quickly pan-fry the fillets for 4 minutes, turning them to brown all sides.

Do not overcook.

Remove the lamb and cover loosely with foil.

Blanch the courgette and corn for about 2 minutes.

Refresh with cold water and drain.

Toss with the red pepper, spring onion, lettuce, bean sprouts and herbs.

Wisk together the dressing ingredients with the juices drained from the lamb and toss into the salad.

Slice the lamb across the grain and toss with the salad just before serving.