STEP 1 Begin by peeling the garlic clove and rubbing it lovingly over the beef fillets, infusing them with a fragrant, garlicky essence. Next, place the steaks in a sturdy sandwich bag and pour in the olive oil, sherry vinegar, and the parsley stalks. Seal the bag and gently smoosh the ingredients together, making sure each steak is evenly coated. Using a rolling pin, give the steaks a few confident bashes to tenderize the meat and help the flavors penetrate deeply. Let these marinate for 1 to 2 hours in the fridge to develop richness and tenderness. STEP 2 While the steaks marinate, prepare the vibrant green piri-piri sauce. Combine all the sauce ingredients—including jalapeno, basil leaves, parsley, spring onions, garlic, vinegar, and a touch of caster sugar—with a tablespoon of water in a blender. Whizz until it becomes as smooth and luscious as possible, ensuring each bite delivers a burst of fresh, spicy zest. This sauce can keep well in an airtight jar for up to a week—perfect for adding a punch to other dishes. STEP 3 When ready to cook, heat a griddle or heavy frying pan over high heat until searing hot. Remove the garlic and parsley stalks from the steaks and lightly brush them off. Season both sides generously with salt and pepper to enhance the natural flavors. Sear the steaks for exactly 2 minutes on each side to achieve a delicious crust while keeping the interior juicy and tender. Once cooked, allow the steaks to rest on a warm plate briefly. Place the ciabatta halves on the plate, toasted-side down, so they soak up the savory meat juices. STEP 4 Thinly slice the rested steaks against the grain for tenderness and pile the slices onto the bottom halves of the ciabatta rolls. Drizzle a generous amount of the green piri-piri sauce over the meat, then top with a handful of fresh rocket for a peppery crunch. Cap with the ciabatta tops and serve immediately for a satisfying sandwich packed with layers of flavor and texture. Enjoy!