Bring a large pot of water to a boil. Submerge the spinach leaves and green chilies for 2 minutes until wilted. Drain immediately and transfer to a bowl of ice water to stop the cooking. Once cool, drain well.

Transfer the blanched spinach and green chilies to a blender. Blend into a smooth, vibrant green purée without adding extra water if possible. Set aside.

Heat 1 tablespoon of oil or ghee in a large skillet over medium heat. Add the paneer cubes and fry until light golden spots appear on the edges, about 3 to 4 minutes. Transfer the fried paneer to a bowl of warm water to keep it soft.

In the same skillet, add the remaining 1 tablespoon of oil or ghee over medium heat. Add the cumin seeds and let them sizzle for a few seconds. Add the chopped onions and sauté until translucent and light golden, about 5 minutes.

Stir in the ginger garlic paste and cook for 1 minute until the raw aroma disappears. Add the chopped tomatoes, turmeric powder, coriander powder, and salt. Cook until the tomatoes soften and oil begins to separate at the edges, about 5 minutes.

Pour the spinach purée into the skillet, stirring to combine with the onion-tomato base. Drain the paneer from the warm water and fold the cubes into the spinach gravy. Simmer uncovered over low heat for 5 minutes.

Stir in the garam masala and crushed kasoori methi. Remove from heat and serve hot.