1. In a large bowl, whisk together the lukewarm milk, sugar, and melted butter. You want the mixture to be warm but not hot, about 37–43°C. Sprinkle the yeast over the top, stir, and let it sit in a warm place for about 10 minutes until it activates and becomes foamy.
Add 480g of the flour and stir with a wooden spoon until the ingredients are combined. Cover the bowl with a towel or plastic wrap and let the dough rise in a warm place for 1 hour, until it has almost doubled in size.
2. Grease two 23 cm round baking pans and set them aside.
In a medium bowl, prepare the filling: mix the brown sugar, softened butter, and cinnamon. Set aside.
3. Return to the dough. Remove the plastic wrap, add the remaining flour (120g), baking powder, and salt, and mix well. Transfer the dough to a clean surface. Keep a little flour nearby in case it sticks, but try to avoid adding too much. Knead for about 10 minutes until it is smooth, elastic, and no longer sticky. It should spring back when pressed.
4. Roll out the dough into a rectangle about 0.5–1 cm thick and spread the filling evenly over the entire surface. Roll the dough up tightly and cut rolls about 8 cm each. Place them in the prepared pans, cover, and let them rise again for 30 minutes.
5. Bake in a preheated oven at 180°C (convection/fan setting) for 25–30 minutes, until golden brown.
For the Icing:
1. In a bowl, beat the cream cheese, melted butter, milk, and vanilla until the mixture is smooth.
2. Gradually add the powdered sugar until you have a uniform frosting.
3. Let the cinnamon rolls cool for 10 minutes and then drizzle with the icing, spreading it with the back of a spoon if desired.
