How to make Aloo Chole Chick peas with potatoes

1 1/2 cup Chick Peas, soaked overnight
8 cup Water
1/4 kg Potatoes, inch sized pieces
1/2 tsp Bicarbonate of soda (baking soda)
1 1/2 tsp Salt
1/8 tsp Mango powder
2 Onion finely, chopped
1/2 cup Ghee or Oil
1 tsp Red Chilli powder
1 tsp Coriander powder
1/4 tsp Haldi powder
1 tsp Paprika powder
1/4 tsp Nutmeg, grated
1/2 tsp Pomegranate powder
1 tsp roasted Cumin seed powder
1 canned of Tomatoes
1 tsp Garlic, crushed
1 tsp Ginger, crushed

 Garnish:
1 tsp Garam masala powder
2 Green Chillies finely chopped
2 tbsp Fresh Green Coriander chopped

Method:

1. Place the chick peas in a large sauce pan with the bicarbonate of soda, water and salt.
2. Bring to the boil, cover and simmer gently for 1 hour until the chick peas are tender.
3. Meanwhile in another sauce pan, heat the ghee or oil and fry the onion until golden brown.
4. Add the garlic, ginger, tomatoes and make a smooth paste using a blender or a food processor.
5. Put it back into the sauce pan and add all the remaining ingredients. 
6. Keep stirring for 5 minutes.
7. Drain the chick peas and add to the sauce pan. Mix them into the sauce. 
8. Simmer until the chick peas are thoroughly tender and have absorbed the flavour of the sauce. 
9. Add the potatoes and the chickpea water and cook for 10 minutes until the potatoes are cooked.
10. Garnish with garam masala, green chillies and fresh green coriander.
11. Serve with Bhature, nan, or Chapati.