Scrub the potatoes and cut the bigger ones into half, then put them in a pan of water and bring to the boil and cook for 15 minutes, or until tender. Drain the potatoes, then season with salt and pepper and squeeze the lemon juice over them.
Meanwhile, finally slice the onion and garlic. Cut the aubergine and red pepper into 2 cm pieces.
Heat 2 tablespoons of vegetable oil in a large frying pan or casserole dish. Add the onion and garlic and cook for 5 to 8 minutes under cover until soft. Add the chopped aubergine and red pepper, put the lid on and sauté for 5 to 10 minutes.
Add the tomato puree and the spices, stir to coat the veggies, then add the stock - enough to cover everything. Cook for 10 minutes, then add the drain chickpeas and cook for another five minutes or so. When you have a nice, silky, thick sauce, add the spinach, put the lid on and steam for another five minutes.
Stir in the cooked potatoes, taste and adjust the seasoning.
Heat it up again to warm through.
Serve with chopped herbs and a squeeze of lemon juice.