Rub beef with thyme and 1 teaspoon freshly ground black pepper. Heat 1 tablespoon oil in a frying pan over high heat. Add beef and cook for 3–4 minutes each side or until browned and cooked to your liking. Transfer to a plate, cover loosely with foil and rest for 5 minutes. Trim fat from beef before thinly slicing.

Meanwhile, place carrot, beetroot, dill, rocket, pepitas, lemon juice and remaining oil in a salad bowl, tossing to combine.

Place yoghurt, horseradish and 1 tablespoon water in a small bowl, mixing well to combine.

Add beef slices to salad, tossing to combine. Divide beef salad among pita pockets, then serve drizzled with yoghurt and horseradish sauce.