Turn the Instant Pot to Sauté mode and heat oil. Add cumin seeds. Sauté for 30 seconds.
Add onions and mix well. Cook covered with a glass lid on for 1 minute. Add tomatoes, mix and cook covered for another minute.
Add turmeric, red chili powder, coriander powder, cumin powder, garam masala and salt. Add potatoes and cauliflower florets. Add 1 tablespoon of water. Mix well.
Put the Instant Pot lid on with pressure valve to sealing. Select Pressure Cook / Manual (Hi) for 3 minutes. Note: Cook for only 2 mins if you like cauliflower to be more firm.
Press Cancel to turn the Instant Pot off. Quick Release and stir gently. Garnish with cilantro. Serve hot with naan, paratha or toasted pita bread.