Whisk dry ingredients together (flour, baking powder, sugar, cinnamon & salt) in a large bowl until combined
Melt butter and milk together in a small saucepan over low heat until the butter is just melted
Pour milk mixture into the flour mixture. Use a spatula to mix together until just combined
Knead the dough for 1 minute on a lightly floured work surface until it comes together. If it starts to feel too sticky, add a touch more flour
Cover the dough with a damp towel and let it rest for 15 minutes
preheat oven to 350 degrees. Liberally grease an 8-inch square baking dish with butter or non-stick cooking spray, set aside
Roll out dough into a 10x14 inch rectangle. Brush dough with melted butter and sprinkle with cinnamon and sugar mixture
Roll up dough starting at the long end, creating a tight log
Slice into 9 rounds
Lay rolls out on the greased baking dish and bake in preheated oven for 25-30 minutes until pale golden brown
Mix icing ingredients together using a hand mixer until fully combined
Allow rolls to cool fully prior to topping with icing