Firstly, rinse the Kohlrabi well. Slice the kohlrabi into quarters of even size and thickness of approximately 2 inches. Let the chopped Kohlrabi dry completely, overnight.
Using a mortar and pestle crush the mustard and coriander seeds gently. Combine the oil, salt, crushed spices, along with Kashmiri chili powder, ground ginger, and asafoetida, in a large plate. I typically use my hands to mix it well.
Add in the Kohlrabi and stir and mix until the spices are well mixed.
Transfer the mixture coupled with Kohlrabi to a glass jar with lid.
Finally, cover the glass jar with a lid and keep it in direct sunlight (in summer) for 5 to 7 days. I typically keep it on a table in the backyard or on a window sill that has direct sunlight. In the case of less sunlight, keep the jar outside for at least 10 days.