If you have some good mangoes in hand, then just remove the peel and seed and blend the pulp to get a puree.
Take dahi, besan, ginger and green chilly in a blender and blend until you get a lumpfree paste.
In a kadhai, heat the oil and add all the spices and heat on a medium high flame, just keep it from burning.
Once the spices start to sputter add the dahi-besan paste, mango puree, water and salt.
Mix well and let it come to a boil.
At this point the kadhi is very thin in consistency and in order to thicken, let it boil over for about 15-20 mins.
Keep stirring it at intervals in order to keep it from burning.
Once you like the consistency it is at, turn of the flame and keep it aside.
Now for the tempering, heat ghee in a small saucepan, add the spices, let it sputter, turn off the heat and then add the chilly powder as it can burn if added over heat.
Pour the tempering over the kadhi and serve with hot parathas, rice. Enjoy!