In a bowl, add besan, chopped green chillies, 1 tbsp kasuri methi, 1 pinch heeng, ½ tsp red chilli powder, baking soda, 2 tsp oil and saunf. Mix well.
Add water to the besan mix and knead into semi-soft dough. Make sure the dough is neither dry nor too wet. Once it is ready, cover and keep the dough aside for 10 minutes.
After 10 minutes, divide dough into 6 parts and roll into cigar-like shape. Apply little oil to your hands if the dough is sticky.
In a pan, boil water and add the rolls in water one at a time. Cook for 8-10 minutes and stir in between. Make sure the water is boiling throughout cooking process otherwise gatte might break.
Once cooked, take the gatte out on a plate and cut into ½ inch pieces. Keep aside. Reserve the boiled liquid.
In a large pan, heat oil. Add cumin, heeng, turmeric, coriander and red chilli powder. Mix well on low flame.
Blend tomatoes, ginger and green chillies to puree and add to the pan with spices. Mix well and cook for 10 minutes or until oil separates.
Now, add curd to the tomato mix, while stirring constantly. Add remaining kasturi methi and mix well. Now, add the reserved boiling liquid according to the required consistency. Mix well.
Next, add salt to taste along with the reserved gatte. Bring to the boil and cook for 10-12 minutes.
Once cooked, turn the heat off, add garam masala and mix well. Garnish with coriander and serve hot.