Pressure cook them for 5 - 6 whistles or until soft. We need them to be overcooked or mushy for the recipe.
Boil the potatoes. Once cooled to room temperature, remove the skin and mash them completely. Hot potatoes won't bind well.
Add salt and mix well. Make balls and press them to form disc-like structures or patties.
Greeze a pan with 1 tsp oil. Place the tikkis on pan. Shallow fry both till they turn crispy and golden. Flip gently as they are soft.
Remove from pan and keep aside to assemble with other ingredients.
Take a deep plate. Place 1 - 2 aloo tikki. Add 5 tbsp ragda. Add in green chutney and sweet chutney, finely chopped onion, green chillies, coriander leaves, curd. Add chat masala, garam masala, salt, black salt, curd (optional) and mix well.
Sprinkle sev and papdi (I didn't have papdi so i have skipped this).