Peeling the medium-sized arbi, and then quarter them into large, elongated pieces, or cut into discs if you prefer.
In a pan, heat oil over medium heat. After 90 seconds when the oil is hot, stir-fry the taro for about 7-8 minutes until they turn a light golden color all around. Once done, remove the stir-fried taro pieces and set them aside.
In the same pan, add a tablespoon of oil. After heating for about 60 seconds, when the oil is hot, add ajwain seeds and cumin seeds and state for about a minute until aromatic.
Now, add grated ginger, minced green chilies, and finely diced yellow onion. Cook for about 5-6 minutes or until the onion becomes translucent.
Add diced tomato, ground coriander, amchur (mango powder), asafetida, turmeric powder, Kashmiri red chili powder, and salt to the pan. Mix everything well and cook until the tomatoes soften, and the mixture thickens.
Return the fried arbi pieces to the pan. Ensure they are well coated with the spicy tomato mixture. Pour in water, and continue to cook covered for another 5-7 minutes, making sure the taro is fully cooked and tender inside.
Place the cooked arbi in an attractive serving dish and garnish with fresh cilantro leaves and thinly sliced green chilies if desired.