Grind mustard seeds, fennel seeds, cumin seeds and fenugreek seeds.
In a bowl mix all the powdered spices like black salt, chat masala, red chili powder, turmeric, and coriander powder. Add the ground powder to this and mix. Taste and add table salt if needed.
Wash and pat dry the okra. Cut the stems on both side and slit longitudinally.
Stuff each okra with the pickle powder and keep aside.
In a pot add oil, sliced onion and okra.
Stir fry on medium to high flame until the okra is changes colour. Now lower the flame, cover and cook on low heat until soft and tender.