For the dough, heat the milk, butter and sugar in a medium saucepan over medium heat. Only heat long enough to allow sugar to dissolve-do not allow mixture to boil. Set aside and let it cool to lukewarm.
Sprinkle the yeast on top and let it sit for one minute.
After one minute, add 8 cups of the flour. Stir until combined, cover with clean tea towel and set aside in a relatively warm place for one hour.
In a separate bowl combine the remaining one cup of flour, baking powder, baking soda and salt and whisk together.
After one hour, add the flour mixture to the dough. Use dough right away or place in a mixing bowl and refrigerate for up to 3 days.
To assemble the cinnamon rolls, remove half the dough and place on floured baking surface. Roll the dough into a large rectangle.
To make the filling, pour 1 cup of the melted butter evenly over the dough.
In a separate bowl, combine the 2 cups of sugar and 1/4 cup of cinnamon and whisk together. Generously sprinkle half of the mixture over the butter.
Then carefully begin at one end of the dough and begin tightly rolling the dough towards you. When you reach the end pinch the seam together.
Using a sharp knife, twine etc slice the cinnamon rolls into 1 1/2 inch slices. Each log should produce about 18 rolls.
Place the sliced rolls into desired baking pan, cover with a kitchen towel and set aside to rise for at least 20 min.
Preheat oven to 375F. Once rolls have reached desired size, remove the towel and bake for 13-17 minutes. While the rolls are baking, make the vanilla icing!
The easiest way to make this icing is using a mixer, in my opinion. So add the powdered sugar, milk, melted butter and vanilla. Mix together using the whisk attachment until smooth.
After the rolls are done baking, allow them to cool for ~10 minutes then generously pour the icing over the top, being sure to get it all around the edges. Grab a fork and plate and enjoy!