Heat oil in a wide pan on medium-high heat.
When the oil is hot add cumin seeds.
When the cumin seeds splutter, add onions. Sauté until golden. Stir occasionally. Next add in ginger garlic paste and serrano peppers and let it sauté for a minute.
Then add tomatoes, ground coriander, ground turmeric, garam masala powder, red chili powder, and salt.
Stir to combine and sauté for 3 to 4 minutes until the tomatoes become soft and mushy.
Stir in the air fried eggplant. Turn the heat to low and simmer the Baingan Bharta for about 10 minutes until well cooked and well combined.
Once done, turn off heat and add lemon juice and cilantro.