In a pan, add the garlic, ginger, green chilies, onions with tsp of oil and sauté them. Add the spinach and cook them. Turn off the heat. After it cools down run into a mixer or a blender.
Boil the potatoes and cut into cubes. Add turmeric, salt and mix them.
Take 1tsp of oil in a pan and sauté the cumin seeds. Once the cumin splutters add the spinach paste and let it boil for few minutes. Now add the boiled potatoes, garam masala, coriander powder, cumin powder, red chili powder, and salt for taste. Add water only if it is needed. Cook for 5-10 mins covered until the potato absorbs the flavor.