Remove sinew from Lamb fillets and cut to size. About 8-10cm in length is perfect.
Combine ingredients for the marinade and pour over lamb making sure fillets are totally coated. Marinating for a minimum of 2-3 hours is preferable. Overnight even better.
Place lamb in a hot non stick pan or griddle (save as much of the marinade in the bowl as possible) and cook on a medium heat turning only once for around 2 minutes on each side. Medium rare is best. There is no need to oil your pan.
Remove from pan and allow to stand for 3-4 minutes before slicing. This will allow enough time to toss your salad.
Combine salad ingredients saving half the feta and drizzle with a little olive oil. Top with sliced lamb fillets and pour the remaining marinade over the top. Crumble remaining feta as a garnish and serve.