In a small jug with spout, stir the natural yogurt, toum (garlic sauce), lemon juice, and salt together, taste, adjust to suit your palate, and refrigerate until ready to serve.
In a small bowl or shaker combine the dried spices and set aside; you’ll use half the spice mix when you pan fry the cauliflower and half when you fry the chickpeas.
Add the teaspoon of vegetable oil to a small frying pan, just enough to coat the surface, heat over low heat until shimmering, and add the pistachios. Fry for a minute or so, shaking the pan continuously, to crisp up the nuts and brighten their colour, taking care not to let them brown or burn. When done, transfer to a small dish.
To a large frying pan, add 2 tablespoons extra virgin olive oil and heat over medium until shimmering. Add the cauliflower florets, diced stalks and half the spice mix, stir to thoroughly cover the cauliflower in spices, and fry, stirring frequently, until golden-brown. Transfer to a bowl.
To the same pan, add another 2 tablespoons olive oil and finely diced onion, and fry until soft and translucent. Add the drained chickpeas and remaining spice mix, stir to combine, and fry until the chickpeas are soft, adding a little water if needed. Add the currants, return the cauliflower to the pan, stir to combine well, and turn the heat off.
In a fry pan, warm the flatbreads or mini naan. Generously spread each with hummus, pile on the spiced cauliflower and chickpeas, pour on the garlic yogurt sauce, sprinkle on the ground sumac, toasted pistachios and fresh flat-leaf parsley or fresh coriander and serve immediately.