Cook the potatoes. Pressure cook the potatoes and keep aside.
Temper. Heat 1 tablespoon of butter in a pressure pan. Add the jeera, bay leaf, ginger and green chillies, then the onions and 1 teaspoon of salt.
Cook the tomatoes. Add the tomatoes, 1 teaspoon of salt, hing and turmeric. Add 1 cup of water and mash.
Add the masala and vegetables. Add the chilli powder and pav bhaji masala. Add the carrots, beans and 1 1/2 cups of water. Pressure cook for 1 whistle.
Mash. Mash, then add the cooked potatoes and mash again. Add the coriander, peas, more salt if needed and the raw mango powder. Finish with 1/2 tablespoon of butter.
Serve. Toast the pav with butter and serve with the bhaji, chopped onion, coriander and lemon wedges.