Wash and soak dried green peas overnight.
Drain the water and cook peas with 3 cups water in pressure cooker for 3 whistles or until soft and keep it aside.
Grind all the ingredients mentioned under "for dry spice blend" in blender to powder and keep it aside.
Heat 1 tbsp oil in a pan.
Add onions and cook until soft, now add green chillies, ginger garlic paste, tomatoes and cook until soft, turn off the heat.
Allow the veggies to cool down completely, grind to a smooth paste.
Heat the same pan, add the ground onion tomato paste, water, ground spice mix, coriander powder, garam masala, chilli powder.
Also add mashed potato , salt. Stir well and cook on medium high heat for 10-15 minutes and turn off the heat.