In mortal & pestle, add fennel seeds, yellow mustard seeds, crush coarsely & set aside.
In boiling water,add carrots,radish & blanch for 3 minutes.
Turn off the flame & let vegetables stay in water for 4-5 minutes then strain & rinse with cold water.
In a bowl,add blanched vegetables,salt,red chilli crushed,turmeric powder,coarsely crushed fennel seeds & mustard seeds,vinegar & mix well,cover & let it rest at room temperature for overnight.
Take out in a dry & clean jar.
Add lukewarm water,mustard oil & mix well,cover tightly & keep in sunlight during the day for 2-3 days.
Repeat process for 3-4 days.
Mix well occasionally.
Once pickle (achar) is ready it can be stored for up to 2 weeks on kitchen counter & up to 3 months in refrigerator.