1. Soak 1 cup masoor dal / red lentils in water for 8 hours.
2. Transfer in a mixy jar, add 2 green chillies, 2 garlic cloves, 2 gms ginger. blend to a smooth paste.
3. Transfer blended paste to a mixing bowl. add 1/4 tsp salt, a pinch of hing / asafoetida, a pinch baking soda, 1/4 tsp cumin seeds. mix well.
4. In a pan, add 125 ml oil. once it is hot, add small round pieces of batter into oil to make vadas. fry till golden brown. remove and keep aside.
5. In a pan, heat 30 ml mustard oil . add 5 cloves of chopped garlic. saute till it is cooked.
6. Then add 500 gms sliced onions, 2 gms ginger paste, 1/2 cup chopped tomatoes, 1/2 tsp salt, 1/2 tsp turmeric powder, 1/3 tsp cumin powder, 1/3 tsp coriander powder, 1/4 tsp red chilli powder. add 1 tsp water and cook till rawness of spices goes away and tomatoes turn soft and mushy.
7. Add 200 gms potatoes cut into cubes. fry and cook for around 3-4 minutes.
8. Then add 200 ml water and cook on medium flame for 10 minutes.
9. Once water boils add the musur dal'er boras and cook on low flame for 5 minutes.
10. Finally add 1/4 tsp garam masala powder, chopped coriander leaves.
11. Dal'er bora jhol is ready to be served.