Peel and slice your onions, cut tomatoes, and peel and cut potatoes.
In a pot, add oil and onions, and cook over high heat until the onions are soft and the edges of the onions start getting brown.
At this point, lower the heat and add ginger and garlic paste. Mix and cook for 1 minute.
Add chopped tomatoes and all of the spices.
Keep cooking on medium heat for about 5 minutes. If your masala is too dry, add 2 tbsp of water.
Use the wooden spoon to break down tomatoes. Once everything is well incorporated and the oil separates from the masala. Add chicken, and after about 3-4 minutes, add potatoes.
Cook on high heat for 7-8 minutes while mixing now and then to avoid burning and even cooking over medium heat.
Once the chicken turns its color from pink to white, add water and cover the pot. Change the heat to high.
After the first boil, lower the heat to medium-low and keep cooking for 18-20 minutes or until chicken and potatoes are fully cooked through.
Add cilantro and enjoy with white rice and a side salad.