Remove seeds from cardamom pods and grind using a mortar and pestle. Set aside.
Blend garlic, ginger, and chilies with 3 tablespoons of cold water using a stick blender or food processor until smooth. Set aside.
Heat a large pan over medium-high heat and add 1 tablespoon of vegetable oil.
Add 1 teaspoon each of coriander and cumin seeds to the hot oil, allowing them to sizzle for a few seconds.
Add 1 teaspoon ground cumin, ground cardamom, and 1/8 teaspoon ground turmeric. Cook for 1 minute.
Add the garlic, ginger, and chili paste, 1 can of chopped tomatoes, the remaining water, 1 halved and quartered mushroom, and 250 grams of trimmed okra. Mix well.
Bring to a boil, then reduce heat, cover, and simmer for 5 minutes.
Uncover and cook the curry for an additional 10 minutes or until the okra is tender.
Serve hot, garnished with 2 tablespoons of chopped cilantro, accompanied by rice and a tangy Indian relish.