Prepare the vegetables: break the Cauliflower into bite-sized florets, peel and dice the Potato into 1–1.5 cm pieces, finely chop the Onion and Tomato, slit the Green Chili, and mince the Garlic and Ginger.
Heat a wide, heavy skillet over medium heat and warm the Mustard Oil until hot (you may let it smoke briefly then turn the heat down slightly).
Add the Cumin Seeds to the hot oil and let them sizzle for a few seconds, then sprinkle in a pinch of Asafoetida and stir.
Toss in the chopped Onion and sauté until soft and translucent, about 5–7 minutes.
Add the minced Garlic and Ginger and cook for another 1–2 minutes until fragrant.
Stir in the chopped Tomato and the slit Green Chili; cook until the tomatoes break down and the oil begins to separate from the mixture, about 4–5 minutes.
Mix in the dry spices: Turmeric Powder, Ground Coriander, and Kashmiri Red Chili Powder, and season with Salt; cook the spice mix for a minute to bloom the flavors.
Add the diced Potato and Cauliflower to the pan, toss thoroughly so the vegetables are well coated in the spice-onion mixture, then pour in about 1/2 cup of Water. Cover and simmer on low-medium heat for 12–18 minutes, stirring occasionally, until the potatoes and cauliflower are tender but not mushy.
Once the vegetables are cooked, uncover and increase the heat briefly to evaporate any excess liquid if needed; sprinkle in the Garam Masala and Amchur, check and adjust Salt to taste, and give everything a gentle toss.
Turn off the heat, garnish with chopped Cilantro, and serve the Aloo Gobi hot with flatbreads or rice.
