Wash and soak dried peas overnight or for 8 hours in water.
Drain water from peas and cook in pressure cooker with 3 cups fresh water and salt for 4 whistles over medium flame or until peas turn soft. Do not drain water from cooked peas; use them with water when required in next steps.
Heat oil in a pan or kadai over medium flame. Add mustard seeds and cumin seeds; when mustard seeds begin to sizzle, add asafoetida and curry leaves and sauté for approx 10 seconds. Add chopped onion and sauté until light brown. Add minced garlic and crushed green chili–ginger and sauté for a minute.
Add chopped tomatoes and cook for approx 3 minutes. Add garam masala, red chili powder, turmeric powder and coriander powder and cook for 30 seconds.
Add cooked peas (along with water in which they are pressure cooked) and mix well. Add lemon juice and jaggery and mix well.
Mash few peas with a back of spoon to make it thick. Add 1½ cups water and mix well.
Add chopped potatoes (boiled), salt and mix well.
Cook it over low flame for 8-10 minutes or until it turns thick. Takeaway kadai from flame or heat source.
Serve it with aloo wada or samosa with onions on top