In a small bowl, activate the yeast by mixing it with warm milk and a teaspoon of sugar. Let sit until frothy, about 5 minutes.

In a large bowl, combine flour, remaining sugar, and cinnamon. Add melted butter, activated yeast mixture, and mix until dough forms. Knead for about 5 minutes.

Cover the dough with a damp cloth and let it rise in a warm place for 1 hour or until doubled in size.

Preheat the oven to 350°F. Roll out the dough into a rectangle. Spread softened butter over the surface and sprinkle with brown sugar and more cinnamon if desired.

Roll the dough tightly from the longer side to form a log. Slice into 8 equal pieces and place into a greased baking dish.

Bake for 25 minutes or until golden brown. While baking, prepare the frosting by mixing powdered sugar, softened butter, and vanilla until smooth.

Remove the cinnamon rolls from oven, let cool slightly, and spread the frosting over the top before serving.