Drain the chickpeas and add to a pan along with a litre of cold water and a tsp of salt. Bring to a simmer and cook for 10 mins until the chickpeas are soft but not falling apart.
Meanwhile, heat 100ml of olive oil in a large pan over a medium heat. Separate the layers of the pittas and cut into roughly 2cm squares.
Fry in the hot oil until golden and crispy. Remove from the pan onto a plate lined with kitchen paper and sprinkle generously with sea salt and 1 tsp of sumac. Set side.
Wipe the pan clean. Drain and quarter the artichokes (they might come quartered already). Heat a glug of olive oil in the pan over a medium-high heat and fry the artichokes cut side down until golden brown,
Remove from the pan and set aside. Toast the pine nuts along with a splash of olive oil in the same pan until golden brown. Add the remaining sumac and chilli and take off the heat.
Mix the yoghurt with the juice of the lemon, the tahini, 4 tbsp of cold water and a pinch of salt. Set aside.
To assemble, place a layer of the crispy bread onto a large bowl or plate, top with a few spoons of the tahini yoghurt, a few spoons of the chickpeas and a few pieces of artichoke.
Repeat in layers and finish by pouring the pine nuts and olive oil over the top.
Finely chop the mint and sprinkle over.