Preheat oil in frying pan on medium heat. When oil is hot, add nigella, coriander seeds, fenugreek seeds, and fennel seeds. When seeds begin to crackle, add turmeric powder and okra. Stir-fry for five minutes. Add cayenne pepper and cumin.
Reduce heat to low and cook for 10 to 15 minutes or until tender. Add onion and red pepper. Stir-fry for five more minutes. Add salt and black pepper. Cook until moisture is gone from okra (five to seven minutes).
Garnish with Garam Masala and dry mango powder.