Potato Buns

Ingredients

• 4 buns
• 3 potatoes (boiled)
• 1 small onion (very finely chopped)
• 1 tsp ginger (grated)
• 1 green chilly (finely chopped)
• fresh coriander leaves (chopped)
• 1/2 tsp red chilly powder
• 1 tsp chaat masala
• 1/2 tsp garam masala
• salt to taste
• 4 tbsp oil
• tomato ketchup for serving