Slit the green chillies and hollow each and every chilly
Now heat the mastard oil on a very hot temp then turn off the flsme and keep the hot mastard in a bowl
Take another bowl and add salt, mastard powder, fennel, fenugreek, asafoetida and 2tsp hot mastard oil and mixx well to a thick paste
Now fill the mixture in chillies and keep in a plate
Now dip the chillies one by one into mastard oil and put them in a glass jar
Pour all the left mastard oil on the chillies and cover with cotton cloth and keep it in the sunlight for a week
Green chillies pickle is ready