Heat oil in a pan over medium heat. When oil is hot, add heeng, raai, cumin seed, and red chilies.
As soon as the rai begins to pop, add potatoes, stir, and fry the potatoes until they are brown.
Add turmeric, cumin powder, coriander powder, red chili powder, and sugar.
Stir once or twice, and then add peas.
Add 250 ml of water and 1 tspn of salt. Bring to boil
Cover and reduce the heat to low and cook on slow flame for 10 mins.
Stir in grated tomatoes and remaining salt.
Simmer gently uncovered for 10 more minutes.
Garnish with cilantro leaves.