In a small saucepan over low-medium heat, cook together 3 tablespoons milk with 2 tablespoons of flour, whisking constantly, until a thick paste forms. Remove and cool completely. In a microwave safe bowl, heat together the remaining 3/4 cup whole milk with the brown sugar until it is about 110 degrees, or warm to the touch. Stir in the yeast, and set aside until puffy and bloomed.
Beat together the cream cheese, powdered sugar, milk, vanilla extract, and salt until a thick, smooth frosting is formed. Spread generously on top of the rolls once they have cooled for about 5 minutes. Enjoy the frosted rolls warm!