Soak channa dal 4 to 5 hours or overnight. Drain it add it to blender, now add the other ingredients and grind it to a little coarse mix, dont add water. Now remove it to a bowl add some salt and mix well. heat oil for deep frying, drop small dollops of this mix and fry till golden. Remove it to paper towel, and transfer it to a bowl, pour warm water over it and let it sit for 5 mins. Now drain them and set aside.
Grind coconut and fennel to a smooth paste. Set aside.
Heat oil in a kadai. Add in fennel, cinnamon and kal paasi. Saute it for 30 sec.Add in onions, curry leaves and chillies. Saute it for couple of mins.Add in ginger garlic paste and saute it for a min.Add in all spice powder and mix well.Add in tomatoes and mix well. Pour some water and cook it for 5 mins or so till it is completely cooked. Take this in a blender(i removed the chilli before blending) and puree it.
Now heat 2 tblspn of oil in a kadai, add in cumin seeds and let it sizzle. i added the reserved chilli too.Add in the ground masala and cook it for 10 mins or till oil separates.Add in 2 cups of water, coconut paste and mix well.Once it reaches a boil add in drained vada and mix well.Let this simmer for 5 mins
Add in chopped coriander leaves and mix well. Serve with idli, dosa or set dosa.