Boil potatoes with the peels on so they don't get waterlogged. They should just be done, not mushy. Cool, peel and either chop in small cubes or crush with your fingers into pea-size pieces. I like doing this step by hand, it is satisfying somehow and easier to control the size that works best for the dish you are making. Alternately, instead of boiling the potatoes cut into 1/2-inch cubes, and place on a lined baking sheet with 2 tablespoons of oil. Roast at 425°F (220°C) for 20 to 24 minutes, stirring halfway through. Or you can microwave the potatoes, 5 minutes on each side. Boom!
Heat ghee or oil over medium-high heat in a large frying pan, kadai or wok. Sizzle the mustard and cumin seeds until they pop, change color and become fragrant, about a minute or two.
Add onions, curry leaves, and a 1/2 teaspoon of salt. Sauté until the onions are soft and slightly golden, 3 to 5 minutes. Add the green chili, ginger garlic paste, hing (if using), and red pepper. Mix well and fry for 2 to 3 minutes.
Turn up the heat to medium-high and add crushed or cubed potatoes, garam masala, 1/2 teaspoon of salt, amchur or lemon juice, and water (unless your potatoes and mushy and waterlogged). Cook, stirring frequently for 4 to 5 more minutes, and remove from the heat. Garnish with coriander leaves. Taste for the usual need for salt, heat, and acid (lemon). Serve with rice or bread.
Notes
This is an intensely flavored potato masala that works great as a filling or a topping.If you would like a mildly spiced mixture, halve or eliminate the garlic ginger paste and onions. Skipping some or all of the chilies would get you there as well.
Curry leaves add herbaceous, anise, and citrus notes to a dish. curry. If you can’t find them, you can add 1/2 teaspoon of lime rind. The result won't be the same but the zest can add some of the citrus notes you get with the real thing. Buy unwaxed fruit.
If you want to make this dish as a potato salad, leave the potato chunks larger than you would as for a filling for samosas, or a topping of a pizza.
Save time by making the masala while the potatoes are cooking.
If you like, you can substitute 6 ounces of cooked green peas, for 6 oz. of potato; add peas to the mixture along with the potatoes.
Potato masala is a dry curry.If you are wanting something with more sauce, add a half a cup of puréed or chopped tomato after the ginger garlic paste. Cook for 2 to 3 additional minutes, then proceed with the recipe.
Try finding small to medium potatoes of roughly the same size, so they finish cooking at the same time.