Combine chilli flakes, fresh herbs, lemon zest, and a generous pinch of salt and pepper. Arrange lamb cutlets on a large plate or shallow baking dish and sprinkle both sides with the herb mixture. Press the chops with your fingers to work the herbs into the meat. Drizzle cutlets with olive oil, turn to coat, and set in the fridge for approx. 30 mins before cooking.
Preheat a heavy-based skillet or barbecue to medium-high. Cook the cutlets for 2 minutes each side for pink, juicy meat, or a little longer if you prefer your cutlets well-done. Transfer to a clean plate to rest, and drizzle with lemon juice.
Toss together the feta, cucumbers, tomatoes and rocket and arrange over a platter. Top salad with lamb cutlets and the resting juices. Serve with tzatzki and lemon wedges.