In Iran an aubergine purée is almost always part of a meze spread and it is usually my favourite dish. Cyrus, the wonderful cook at my local Iranian restaurant, Sufi, in west London, taught me the trick of making the walnuts we buy here, which are often dry, taste like the fresh ones I remember in Iran. If you are serving this purée as a first course, try to find some Iranian flat bread to accompany it.
A day in advance, put the walnut halves in a bowl and pour enough boiling water over them to cover generously. When the water has cooled, put the bowl in the fridge and leave until you need them the next day.
Heat the grill to its hottest setting. Cut the aubergines in half lengthways and grill them skin side up until the skins are blackened all over. Transfer to a board and leave to cool slightly, then scoop the flesh from the burnt skin with a metal spoon. Discard the skins and chop the flesh roughly.
Peel the onions and chop into small pieces. Peel the garlic cloves and slice across finely. Cut a small slit in each of the tomatoes, put them in a bowl and pour boiling water over them. Leave for 2 minutes or so, then drain, peel off the skin and chop the flesh.
Heat the sunflower oil in a large, deep frying pan over a medium heat, then add the chopped onions and fry until softened and well browned. Mix in the ground coriander, garlic, tomatoes, tomato purée, cayenne pepper and the water. When bubbling, stir around for a few minutes until the tomatoes soften, then add the aubergines and stir for another minute or two. Remove from the heat, season to taste with salt and leave in the pan until cold.
Shortly before eating, drain the walnuts and chop them roughly. Stir into the aubergine mixture and spoon it into a serving bowl. Just before serving, spoon the soured cream on top and drizzle a little olive oil over all.
© 2010 Josceline Dimbleby. All rights reserved.