Boil 500 grams of potatoes until they are cooked but still firm. Peel and mash them coarsely, ensuring some small chunks remain.
Heat 2 tablespoons of oil in a pan. Add 1 teaspoon of cumin seeds and let them crackle.
Add 1 finely chopped green chili and 1 tablespoon of grated ginger. Sauté for a minute.
Add the mashed potatoes, 1 teaspoon of red chili powder, 1 teaspoon of garam masala, 1 teaspoon of amchur (dry mango powder), and salt to taste. Mix well and cook for 2-3 minutes. Set aside to cool.
In a mixing bowl, combine 2 cups of maida (all-purpose flour), 1/2 teaspoon of ajwain (carom seeds), and salt to taste. Add 4 tablespoons of oil and mix well until the mixture resembles breadcrumbs.
Gradually add water and knead the dough until it is firm but pliable. Cover with a damp cloth and let it rest for 20-30 minutes.
Divide the dough into equal-sized balls. Roll each ball into a thin oval shape and cut it in half.
Apply water to the edges of each half and fold it into a cone shape. Fill the cone with the potato mixture and seal the edges by pinching them together.
Heat oil in a deep frying pan or kadai. Once the oil is hot, reduce the flame to medium and carefully slide the samosas into the oil.
Fry the samosas until they turn golden brown and crispy. Remove them from the oil and place them on a paper towel to drain excess oil.