Mash the potatoes lightly. Set aside.
Heat oil in a frying pan over medium heat.
Add cumin seeds and allow to sizzle.
Add onions, green chilies and ginger. Saute, stirring, for about 2-3 minutes or until onions soften.
Add ground turmeric, ground coriander and garam masala. Saute, stirring, for about 30 seconds or until aromatic.
Add potatoes. Season with salt.
Saute, stirring, for about 3-4 minutes.
Add coriander leaves (cilantro). Stir to combine.