Preheat the oven to 180°C fan / 390°F.
To prepare the aubergine, slice thinly widthways, stopping about 2cm from the bottom so that they hold together; place on a large baking tray.
In a small bowl, combine the paprika, cumin, za'atar, olive oil and a generous pinch of salt. Pour over the aubergines and use a pastry brush to spread the mixture in between the slices. Place the tray in oven and cook for 40–45 minutes, until tender.
To make the tomato ragu, warm the olive oil in a shallow casserole dish set over medium heat. Add the onion, garlic and a pinch of salt; cook for 5–10 minutes until softened. Stir in the paprika, harissa, tomatoes, tomato purée and vinegar; half fill the empty tin with water and pour this in too. Bring to a simmer; cook for 15–20 minutes until rich and glossy.
To make the topping, place all of the topping ingredients in a food processor and blitz until you have chunky breadcrumbs.
Once the aubergines are cooked, remove from the oven and transfer to the casserole dish; scatter over the breadcrumbs. Place in the oven and cook for 5–10 minutes until golden. Serve with a drizzle of tahini and fresh basil.
