Thoroughly clean and dry the eggplants. Cut into 1cm pieces and place in a colander, sprinkle with salt, and stand for two hours.
After two hours, shake off any salt, and squeeze the eggplant to remove any excess liquid. Pat dry with paper towels.
Place a small frypan on medium heat and add the first measure of cumin seeds and the fenugreek seeds. Toast the spices until they become aromatic then remove from the heat. When cool enough to handle grind to a fine powder. Set aside.
Heat 100ml of the sesame oil in a pan over a medium heat, and add the eggplant. Make sure you only have one layer in the pan, so you may need to do this in batches. Fry the eggplant for five minutes, tossing frequently, or until the eggplant takes on a light golden colour. Place fried eggplant and any remaining oil into a glass bowl.
Add the chilli powder, ground cumin, fenugreek and garlic to the eggplant and mix well.
Heat the remaining oil in the pan, and when hot, add the mustard seeds, the second measure of cumin seeds and the dried chillies. Fry for one minute, or until mustard seeds start to pop. Remove from heat and pour over the eggplant mixture. Mix well.
Allow mixture to cool enough to handle and transfer to a sterilised jar.
Keep in a cool, dark place for two days, then the pickle is ready to serve.
notes
Indian sesame oil is called gingelly oil, and is not the same as the Chinese variant, being less intense in flavour. A vegetable oil could be used as a substitute.
This pickle will only keep for around two weeks after opening. It must then be kept in the refrigerator.