For the dough : I don't get oat flour here, so I powdered rolled oats in my grinder and used this. Dissolve the honey and the yeast in the warm water and allow the yeast to prove. Put all the other ingredients for the dough in the food processor (or in a bowl, if kneading by hand) and run a couple of times to mix well.
Pour in the yeast-honey mixture and enough water to make a soft, smooth and elastic dough. Shape into a ball and place in a well-oiled bowl, turning the ball of dough so it is coated with the oil. Cover and allow to rise till double in volume (about an hour).
For the filling : Do not mash the potatoes into a paste. Just mash well, till slightly lumpy. You can do this by breaking up each boiled potato by hand. About 5 to 6 medium sized potatoes should give you approximately 2 cups mashed potatoes.
You can make this filling while the dough is rising, or make it the previous day and refrigerate it.
In a pan, heat the oil and add the mustard seeds. When they splutter, add the ginger and the garlic paste and sauté for half a minute. Then add the onions and chopped chillies, and sauté till they are translucent and beginning to turn golden.
Now add the turmeric, coriander, cumin and garam masala powders and sautxe9 for a minute on low heat. Add a quarter cup of water, stir and add the frozen peas and the salt. Simmer for a couple of minutes till they're cooked. Add the mashed potatoes and mix well, cooking for about two minutes. Turn off the heat. Add the chopped coriander and mix well again. Let it cool. Then divide this filling into 6 equal portions. Each portion will measure about 2 to 3 tbsps.
To make the bolsos : Divide the dough into 6 equal portions. On a lightly floured surface, take one piece of dough and roll out into an approximately 4" by 4" square (or a circle). Place one portion of filling on one half of the dough square/ circle leaving about 1/4" of dough free at the edges. Moisten this edge with water and fold the unfilled half over the filling. Seal the edges by pinching together well so that it doesn't open up while baking. Place with the pinched seam down and you should have an ovoid shaped roll. Repeat with the remaining dough and filling, cover and allow to rise slightly for 20 minutes. Brush with milk (or egg wash) and place on a greased sheet. Bake at 200C (400F) for 20 to 25 minutes till done and golden brown in colour. Cool on a rack and serve.