Method - Place lamb cutlets in a shallow dish, add 1 tablespoon oil, the rosemary, lemon zest, salt and pepper and mix well. Refrigerate for 2-3 hours. Preheat oven to 190ºC. In a roasting dish, place the fennel and garlic, then drizzle over the remaining oil and season with salt and pepper. Roast for 20 minutes. Meanwhile, heat a grill plate or frying pan until smoking, then add the lamb and cook for approximately 4 minutes on each side. Remove the fennel and garlic from the oven, squeeze the garlic cloves from their skins and discard the skins. Stir through the spinach leaves - the heat from the fennel will wilt the spinach a little - and serve with the lamb cutlets.