Place frozen rolls in a 9x13-inch baking dish, cover with plastic wrap and allow to thaw in the refrigerator overnight. In the morning, combine two dinner rolls and roll into a ball. Using clean kitchen scissors, cut four or five deep slits almost to the bottom of the roll. Repeat with remaining rolls.
Combine melted butter, brown sugar and cinnamon. Using your hands rub the cinnamon/sugar paste all over the rolls, making sure to get inside every slit. Place in a greased muffin tin. Spray plastic wrap with cooking spray and loosely cover rolls. Allow to rise in a warm place until doubled.
When rolls have risen, remove plastic wrap and bake in a preheated 350 degree oven for 15-16 minutes. Carefully remove rolls from muffin tin as soon as they are finished baking. Brush vanilla icing over the warm rolls. Serve.
For the Vanilla Icing: Combine powdered sugar, one Tablespoon of milk and the vanilla extract and stir together until smooth and creamy. If it's too thick, add a little more milk.