Prepare the eggplant: Wash and dry the eggplant.
Cut into small cubes (about ½ inch).
Spread on a clean cloth and leave to air-dry for 1–2 hours so excess moisture evaporates.
Roast the spices: In a dry pan, roast fenugreek seeds on low heat until they smell nutty. Remove and cool.
Roast mustard seeds until they start popping. Cool.
Coarsely grind both into a powder.
Cook the eggplant: Heat half the oil in a deep pan.
Add asafoetida and broken red chilies if using.
Add eggplant cubes and turmeric.
Cook over medium heat until the pieces are soft and lightly browned, stirring occasionally (about 10–12 minutes).
Mix the pickle: Let the eggplant cool completely.
In a large bowl, combine chili powder, ground fenugreek-mustard, and salt.
Stir in tamarind pulp.
Add the cooked eggplant and mix well.
Pour in the rest of the oil and stir to coat everything. Oil should cover the pickle to help preserve it.
Taste and adjust salt or chili.
If you like a hint of sweetness, mix in jaggery.
Store: Transfer to a clean, dry glass jar.
Leave at room temperature for 2–3 days so the flavors meld.
Refrigerate afterward. Always use a clean, dry spoon.