Slice the green apple with its peel on, into long thin slices after removing the core and seeds. You may also slice the apple after frying the brinjal, so that you can cook it before it begins to brown.
Top and tail the purple brinjal (remove the stem and slice a little off the bottom) and cut into slices similar to the apples.
Add half the turmeric powder and half of the fennel powder in the ingredients list, along with a pinch of salt, to the sliced brinjal and mix them in well. The turmeric will stop the brinjal from browning.
Heat the oil in a frying pan or kadai and add the brinjal slices with the powders and salt that you mixed with them. If the brinjals are thinly sliced, it would take 5-8 minutes for them to fry till cooked, on medium heat.
Drain the oil and remove the brinjal from the pan, setting them aside to drain in a colander.
In the same pan and using the left over oil in which the brinjal was fried, add green chillies and then hing/ asafoetida. Sauté for 30 seconds.
Add the apple slices and all the powders as in the ingredients list - the remaining half of the turmeric and fennel powders, the red chilli powder, the cumin, ginger and clove powders. Add some of the salt, being cautious as the apple will cook down a little. You can check and add more salt if required, in the end.
Stir well and sauté on low heat for 10-12 minutes, until the apple is tender.
Add the water, stir and cook for about 5 minutes, or till the apple is cooked.
Add the fried brinjal and gently stir it in.
Check for salt and add more as required. Stir.
Turn off the heat and transfer the Kashmiri Green Apple Brinjal Curry to a serving dish (removing it from the hot pan so that it stops cooking).
Serve with hot rice or with roti.