Heat water in a pot. When it comes to a boil, all the cut cauliflower, carrots and turnips. Cook for 3-4 minutes. Then remove the water and spread them on a clean cloth.
Leave these vegetables overnight or till all the moisture is removed.
Roast fenugreek seeds and mustard seeds.
When cooled, ground them into a fine powder.
Combine this powder with Kashmiri red chilli powder and salt. Keep aside. This is the spice mix for the pickle.
Heat mustard oil till it starts smoking.
Add ginger, garlic and onion paste and cook on medium heat for about 10 minutes till the rawness of all the vegetables is removed.
Add vinegar and jaggery. Cook till the jaggery melts completeley.
Now add the spice mix. Cook for 2 minutes and remove from heat.
Let this mixture cool a bit.
Then add the dried vegetables and chillies (optional) and give them a good mix.
After about an hour, transfer this to any plastic or glass jar with an airtight cover.
Cover and let it rest for 3-4 days, after which, the pickle will mature and will be ready to eat.