Wash and pat dry lemons and green chilli. Remove the top of chilli. Place them in sun for 1 hour.
Now cut lemons in 4 pieces. Apply salt, red chilli and carrom seeds thoroughly in lemons and chillies.
Dry roast fenugreek, mustard, fennel, black pepper and black salt and cumin seeds in a wok and remove in a plate. Allow it to cool. Then coarsely grind in a mixer. Now Heat mustard oil in that wok. Keep aside for 15 minutes to cool. Mix coarsely grinded masala mixture in mustard oil.
Now pour this masala on lemon and chillies and mix well.
Mix it in such a way that lemon pieces and green chilli are coated well with this masala.
Now transfer it in a jar and keep jar in sun for a day. Mix the pickle thoroughly in between. It will be ready instantly. No need to add preservatives as lemon and salt is in the pickle.
Keep it in sun for a day covered its lid tightly.
