For the dough, in a medium pan, heat milk, oil and sugar over medium flame till just below boil. You can scale to 150 degrees. Set aside and allow it to cool until lukewarm.
Sprinkle the yeast & allow it to sit & froth for about 5 minutes. To this mixture, then add 4 cups of flour and stir until just combined using a wooden spoon. Cover it with a kitchen towel or cling film and allow it rise in a warm place.
If you do not have ground cinnamon like me, then grind it yourself. In all probability it wouldn't grind very fine. If it happens with you too, then combine the already roughly ground cinnamon with powdered sugar and grind again.
After an hour, add remaining 1/2 cup flour, baking powder, baking soda, and salt. Stir mixture thoroughly. I used my hands to bring all the ingredients together. You can even refrigerate the dough at this point for up to 3 days.
Prepare a working counter by sprinkling generously with flour. Divide the dough into two.
Take one dough and using your hands, shape it roughly into a rectangle. Then with a rolling pin, roll the dough thin, maintaining the rectangular shape. Ideally the longer sides should be facing you.
Drizzle melted butter over the rolled dough. I used a spatula to evenly spread it.
Sprinkle with sugar and cinnamon. Roll the dough from the longer side toward you as tight as possible for firmer shaped rolls. You may need to use both your hands and proceed slowly. Pinch the seams to seal it. Roll in to a log.
At this stage I refrigerated the rolled doughs overnight as I wanted the sliced rolls to be more shapely.
Grease a rectangular baking dish of 11X9X4 inch. Slice the log in 1/2 inch rolls, one log will give you about 2 dozens of mini rolls. Lay the sliced rolls in the greased pan. Be careful and do not over crowd the pan.
Cover the prepared pan with rolls with kitchen towel and set aside for 30 minutes in a warm place for a second rise. Bake at 190 for 15 to 18 minutes, until golden brown. Don't allow them to become over brown or they will dry up.
While the rolls are baking, in a medium bowl combine all the ingredients of the frosting. Whisk well till smooth. Taste and adjust as per your need. The consistency needs to be thick but still pourable.
As soon as the rolls are out of the oven, generously pour frosting over the warm rolls. Be sure to pour around the edges and top. As they sit, the rolls will absorb flavour from the frosting and get better with time.