Aloo Posto a Bengali delicacy

Ingredients needed for Aloo Posto
500 grams potatoes, boiled, peeled and cubed 
4 dried red chillies
5 green chillies
1 tbsp black cumin seeds
1 tbsp turmeric powder
1 tsp red chilli powder
1 tsp cumin powder
1 cup gram khus khus ( about 200 grams )

How to prepare Aloo Posto?
while boiling potatoes, don't cook them very soft. Remove them from fire when they are almost cooked. Peel them and cut them in to cubes.
Add 1 glass of water to khus khusand leave it aside for 10 minutes. Grind to a paste and keep aside. 
    Heat oil in a nonstick fry pan. Add red chillies, green chillies and cumin seeds. Fry till the jeera splutters.
Add the cubed potatoes little by little and stir gently for 3-4 minutes. All the potato cubes should have hot oil coated and should have started changing shade.
Now add turmeric powder and mix well.
Add 1/2 teaspoon of cumin powder, one teaspoon of red chilli powder, one teaspoon of salt and stir for about a minute.
Then add poppy seeds paste (khus khus) and stir well.
Add a cup of waterand cook till the potatoes are soft and tender.
When the potatoes are tender, increase the flame and dry the extra moisture.
You should be able to break the alu with fingers,it should be soft and cooked well.
Serve hot with rotis or rice .