Add the feta, 2 tablespoon of harissa paste, and the milk to a small bowl. Mash with a fork until creamy and spreadable. For a smoother consistency, blend in a small food processor. If needed, add a little more milk, a teaspoon at a time.
1/3 cup feta, 3 tbsp harissa paste, 2 tbsp milk
Place the steaks on the hot BBQ and cook for approximately 3–5 minutes per side, depending on their thickness and your preferred doneness. Transfer to a plate, cover loosely with foil, and rest for 5 minutes.
While the steak rests, grill the flatbreads for approximately 30–60 seconds per side, until warm and lightly toasted.
3 flatbreads
Thinly slice the rested steak across the grain. Spread the harissa feta over the warm flatbreads, then divide the rocket, radishes, and steak slices between them.
1 cup arugula, 3 radishes
Drizzle the flatbreads with the remaining harissa paste, adjusting the amount to suit your preferred heat level. Serve immediately.
Video
Notes
Keep the flatbreads soft: Warm them just until lightly toasted. Grilling for too long can make them brittle.Cook indoors: Use a hot skillet or grill pan for the steak and a dry frying pan to warm the flatbreads.Make ahead: Prepare the harissa feta, slice the radishes, and wash and dry the arugula the day before. Refrigerate in separate airtight containers. When ready to serve, grill the steak, warm the flatbreads, and assemble.