Heat a skillet and add cumin seeds and fry for 30 seconds. Add the thinly sliced onion and cook stirring often till onion turns soft and light golden.
Add the green chili, ginger and garlic and saute for 1-2 minutes.
Add the spices, black pepper and turmeric and mix until fragrant, about 30 seconds. If the mixture is dry, splash1 to 2 table spoons of water to prevent burning.
Add the chopped tomato, tomato paste and salt and cook till tomatoes turn mushy.
Add the sliced zucchini and coat them with the spice mixture. Cook till the zucchini turns soft and slightly mushy. It may take 12 – 15 minutes. You can also use the spatula to slightly smash the curry.
Add the cashew cream, mix and check for salt. cook for 2-3 minutes and turn off the stove. Finally add some fresh coriander leaves and serve the curry with roti or rice.