Shred cabbage, red onion and some green chilli and mix together. Grate garlic into some yoghurt and toss the lot together. Lay out a flour tortilla and bread with some hummus, place the cabbage on top, then top with mackerel, a sprinkling of za’atar or cumin, a squeeze of lemon and some pomegranate seeds and wrap the whole thing up like a shawarma.