Heat sesame oil(nallenna) in a pan, splutter mustard seeds, fenugreek and curry leaves.
Add chopped ginger, garlic and fry till light brown.
Add turmeric powder, chilly powder, asafoetida powder and salt.
Add mango pieces and stir well.
Remove from flame. Add vinegar and stir again. Pour it into a clean, dry bottle.
If you need, add warm water to the used pan and pour it into the bottled pickle after it cooled.
Its ready to serve the same day after cooled.