In the bowl of an electric mixer, add the milk and sprinkle on the yeast. Let sit until the yeast starts to foam, 1-2 minutes. Stir in the sugar, egg, egg yolk, and melted butter then stir in the flour and salt with a wooden spoon until everything comes together into a ball of dough.
Knead with the dough hook on medium for 8 minutes. Alternately, knead by hand for 8-10 minutes on a floured surface. Lightly oil and large bowl and place the dough inside.
Cover with plastic wrap and a kitchen towel and let rise for 1 to 1 and a half hours or until doubled in size.
On a lightly floured surface, tip out the dough and roll out to a large, long rectangle, about 14 x 20 inches. Spread the butter evenly, all the way to the edges. Whisk together the cinnamon and sugar in small bowl then spread evenly onto the dough.
Roll into a tight roll, and cut into 9 even pieces for an 8 x 8 or 9 x 9 inch pan. If using a 11 x 7 inch pan, cut into 6 pieces for giant rolls or 12 for smaller rolls. Place the rolls into the pan.
Cover loosely with plastic and let rise in the fridge overnight. Or, if you’re wanting to bake right away, cover and let rise at room temperature for 30 minutes to 1 hour, or until doubled.
When ready to bake, remove the rolls from the fridge and heat the oven to to let come to room temperature as the oven is heating up, about 30-45 minutes. Heat the oven to 350°F. Bake for 25-30 minutes, or until slightly golden and just cooked through or the internal temp comes to 190°F.
While the rolls are baking, make the frosting by beating together the cream cheese, butter, powdered sugar, and vanilla (if using) until light and fluffy. Let the rolls cool for 5 minutes, then frost. Enjoy!