To make the vadas.
Boil and mash potatoes. Heat oil in a pan and season with mustard and cumin seeds. You can also add some freshly crushed coriander and fennel seed for flavour. Now add asafoetida and saute finely minced green chillies, ginger and garlic until they lose their raw smell. Now add chopped onion and cook until transcluscent. Add the powders now. Turmeric, coriander, red chilli and cumin powders. Add salt as per taste, squeeze the juice of a lime and garnish with finely chopped coriander leaves. Mix well and make lemon sized balls. Dip these balls into a batter made out of 1cup chickpea flour, 2 tbsp rice flour, salt, chilli powder, and asafoetida. You can also add a pinch of soda bicarb. Fry these balls in hot oil until golden brown. Keep aside.
For the chutneys.
Green chutney: Wash and roughly chop a bunch of mint and coriander leaves. In a blender, take a handful of peanuts, cumin seeds, 3 to 6 green chillies depending upon your spice level, and blend with the mint and coriander leaves to a fine paste. Add minimal water. Add salt, sugar and lime juice as per your requirement. This chutney can be stored in a glass jar in the fridge for upto 10 days.
Sweet tamarind chutney: in a pressure cooker, take a ball of tamarind, a handful of deseeded dates, and equal amount of jaggery. Add water to cover these and pressure cook for 8 to 10 whistles. Once cooled, blend and strain. Add salt, chilli powder, coriander and cumin powders and mix well. You can further cook this until it reduces to a thick paste. This can be stored for even 6 months in the fridge.
Dry coconut garlic chutney: Dry roast one cup of grated coconut until brown. Roast 10 to 15 garlic pods, a handful of peanuts, a teaspoon each of coriander and cumin seeds. Take all these into a mixer once cool and add salt and red chilli powder. Pulse to get a dry chutney powder.
Making the pav buns
Take half a cup of lukewarm water and half a cup of milk and add 2 tbsp of sugar and 2.25 tsp of active dry yeast. Mix well and let it bloom. This takes around 5 to 7 minutes.Add around 4 tbsp of room temperature butter and 3 cups of all purpose flour. I normally use 1.5 cups apf and 1.5 cups of whole wheat flour. Knead well for 8 to 10 minutes until smooth. You can add some flour if required. Place in an oiled bowl and cover with a warm, damp cloth and let it proof. After 2 hours, it would have risen to double. Punch the dough and knead again. Make small balls of the dough and roll it smooth. Place on a baking tray leaving gaps between each other. Cover and let it proof for another 45 minutes. Once the buns have risen, apply some milk on top and bake in a preheated oven for 20 minutes at 180 degrees. Smear some butter on top.
Assembling the vada pav
Take a pav buns and slice it in the middle taking care not to go the entire way. Apply green chutney on one side and tamarind chutney on the other. Sprinkle some dry garlic coconut chutney on the potato vada and sandwich it between the pav bun. Enjoy this filling indian street dish.