Wash, dry, peel and cut radishes into long-thin pieces.
Add 3/4 tsp to the radish pieces, keep salt applied radishes on a tray and place it in direct sunlight. Remove water extracted from the radishes.
Roast methi and ajwain in a pan till they turn light brown, take out roasted spices in a bowl. Once the spices cool off, grind them along with Mustard seeds to make a coarse powder.
Pour oil in a frying pan and heat. Put radishes in hot oil and fry for 2 minutes then turn off the gas. Add hing, turmeric powder, red chilly powder and salt to radishes;mix properly. Now put in the roasted spices and mix thoroughly. After pickle cools a bit pour vinegar and mix well.
Store in refrigerator.