In a bowl, combine the chicken pieces with the lemon juice and a pinch of salt. Allow the chicken to marinate for at least 30 minutes.
Heat the vegetable oil in a large pan or Dutch oven over medium heat. Add the finely chopped onions and sauté until they turn golden brown.
Add the minced garlic and grated ginger, and cook for another minute until fragrant.
Reduce the heat to low and add the ground cumin, ground coriander, turmeric powder, paprika, and garam masala to the pan. Stir the spices for a minute to release their flavors.
Add the chopped tomatoes and green chilies, and cook until the tomatoes soften and release their juices.
Increase the heat to medium and add the marinated chicken to the pan. Cook the chicken for about 5-7 minutes until it is lightly browned on all sides.
Reduce the heat to low and pour in the coconut milk. Stir well to combine the chicken with the coconut milk and spices. Cover the pan and let the curry simmer gently for 25-30 minutes, or until the chicken is cooked through and tender.
Taste the curry and add salt as needed. If you prefer a spicier curry, you can add more green chilies or a pinch of chili powder at this stage.
Once the chicken is cooked and the flavors have melded together, turn off the heat. Garnish the Kuku Paka with freshly chopped coriander leaves.
