Activate your yeast by whisking together the milk, sugar, and butter over medium heat until the butter has melted. Remove from heat and cool to 37 - 39 degrees.
Gently mix the yeast into the milk and cover to let it activate until foamy and frothy.
Let the dough proof in a warm place.
Roll and fill the dough, cutting it into strips or rolling it into a log and cutting pieces.
Store prepared cinnamon buns in the fridge if making ahead, and allow to proof in a warm place before baking.
