Combine the ketchup and next 9 ingredients in a large mixing bowl. Add the coconut and stir to combine. Add the water and stir to combine. Stir in the chicken until thoroughly coated. Set aside.
Heat the ghee or oil in a large skillet until hot. Add the nigella and fenugreek seeds and fry for one minute until aromatic. Add the garlic and ginger and fry for another minute. Add the chicken mixture and bay leaf, bring it to a simmer, reduce the heat to medium, cover, and simmer for 25 minutes, stirring occasionally. Add the cherry tomatoes and chopped cilantro and simmer for another 3 minutes until the tomatoes are tender but still a little "snappy." Add salt to taste.Serve with steamed Basmati or jasmine rice and/or naan.