Cut the tops off the green peppers, then remove and discard the seeds. Cut a thin slice off the base of the peppers, if necessary, to make them stand upright.

Bring a large pan of lightly salted water to the boil. Add the peppers and cook for 5-6 mins. Drain and leave them upside down in a colander.

Cook the potatoes in lightly salted boiling water for 10-12 mins until just tender. Drain, cool and peel, then cut into 1cm cubes.

Put the onion, garlic, ginger and green chillies into a food processor to a puree.

Heat 3tbsp of the sunflower oil in a large, deep frying pan and cook the diced aubergine, stirring occasionally, until it is evenly browned on all sides. Remove from the pan and set aside. Add another 2tbsp of the sunflower oil to the pan, add the diced potatoes and cook until lightly browned on all sides. Remove the potatoes from the pan and set aside.

If necessary, add another 1tbsp sunflower oil to the pan, then add the cumin seeds. Fry briefly until the seeds darken, then add the turmeric, coriander and ground cumin. Cook for 15seconds. Stir in the onion and garlic puree and fry, scraping the pan with a spatula, until the onions begin to brown.

Return the potatoes and aubergine to the pan, season with salt, pepper and 1-2 pinches of cayenne. Add the remaining water and 1tbsp lemon juice and then cook, stirring until the liquid evaporates. Preheat the oven to 190ºC/375ºF/Gas 5.

Fill the peppers with the spiced vegetable mixture and placed on a lightly greased baking tray. Brush the peppers with a little oil and bake for 30-35 mins until they are cooked. Allow to cool a little, then sprinkle with a little more lemon juice, garnish with the coriander and serve.