Marinate the prawns with red chilli, turmeric powder, vinegar and salt. Keep aside for half an hour.

Heat vegetable oil in a deep pan; deep fry the prawns in batches and keep aside. Do not overcook the prawns or it will turn rubbery.

Heat 2-3 tbsp of gingelly oil in a wide pan; crackle mustard seeds and then add the fenugreek seeds.

Add the garlic, ginger and curry leaves; sauté till lightly browned and raw smell is removed.

Make a paste using red chilli powder, turmeric powder and 1 tbsp vinegar. Add water if necessary to make the paste.

Add this paste to the pan and sauté for another minute. Add ½ cup water and bring to boil.

Then add the prawns and mix well. Season with salt if necessary. If you wish to have more gravy to the pickle, you may add more water.

Cook on medium heat for about 2 minutes and then remove from heat.

Allow to cool completely and then add asafoetida and the remaining 1 tbsp vinegar.

Transfer to a clean sterilized bottle and pour the remaining gingelly oil on top.

Let the pickle sit at room temperature for a whole day and then refrigerate it.