Iyengar bakery style stuffed potato buns

These buns are fresh off the oven. I just made these, ate one.....have a plate with another one on my side.....and am typing out this recipe as I take generous bites. These are seriously so soft,so good and so tasty......just like you would get at any of the Iyengar bakeries in Bangalore. I have decided that whenever the craving for these strikes, I am making them at home, and not buying them. They are that good.
Before I tell you again how good they are, I must thank Lata for giving me this recipe, and also for being kind enough to convert the recipe from measurements in grams to cups. Thank you, Lata.
Before I start raving about how good these are AGAIN, let us get to the recipe.
What you need:
Maida/All purpose flour - 2 cups, heaped
Active dry yeast - 1 tbsp
Salt - 1 tsp
Sugar - 3 tbsp
Milk - 2/3 cups
Softened butter - 2 tbsp (heaped)
Vanaspati/Vegetable shortening - 1 tbsp
Curd/Yogurt - 1 tbsp
For the masala/stuffing:
Potato - 3 small, cooked, peeled and mashed
Carrot - 2 small, cooked and mashed
Onion - 1, chopped fine
Turmeric powder - 1/2 tsp
Oil - 1 tbsp
Garam masala - 1/4 tsp
Corriander leaves - a little, chopped fine

Heat oil in a pan. Add the onions and saute till they begin to brown. Add turmeric powder, mashed vegetables, garam masala and salt. Add 1/4 cup of water. Stir well and then heat until moisture evaporates completely and the masala comes together. Garnish with corriander leaves and keep aside.

To make buns:
Take the maida,salt and sugar(keep aside a tsp for proofing yeast)in a large mixing bowl. Add a tsp of sugar and a little lukewarm milk to the yeast. Keep it covered until it starts to bubble. Make a well in the centre of the flour and pour the yeast in. Mix in butter, vegetable shortening, milk and yogurt. Knead to a soft, pliable dough. Keep covered until it doubles in volume. This take about an hour and a half. Punch down and divide the dough into eight equal balls. Divide the prepared masala into 8 balls that are half the size of the dough balls. I had some left over masala which was tasty enough to eat on its own. Now, take one ball of dough in your hand and flatten it into a circle. The dough has enough butter in it to not stick to your hands. Place the masala ball in the centre and then pull the sides to close the masala. Flatten and smooth into a circle again. Place it in a greased baking tray with the closed side facing down.
Cover with a wet towel and set aside for 15-20 minutes for it to rise again. Meanwhile, preheat your oven to 175 degrees. All my baking is done in a convection microwave oven. I do not have a preheat function in my oven....so usually I just turn it on for 10 minutes at 175 degrees and that does the trick.
Just before baking, apply an egg wash to the top of each bun. To prepare egg wash, lightly beat an egg, along with a tbsp of water and then brush it over the top of the buns. Bake for 20-22 minutes or until the top turns a nice brown and the centre, when touched, has a nice spring to it.
Eat hot off the oven, or warm up and serve later.

This is my first post for Blogging Marathon#6 week 2, under the category picnic food.
Check out the Blogging Marathon page for the other Blogging Marathoners doing BM#6 hosted by Srivalli