For the cupcakes

1. Preheat your oven to 350F (175C) and line your cupcake pan with 12 papers.
2. Sift flour, baking powder, salt, and ground cinnamon into a small bowl. Set aside.
3. In a large mixing bowl beat together butter and sugar with an electric mixer until light and fluffy, about five minutes.
4. Beat in the eggs one at a time, followed by the vanilla extract. Scrape down your bowl and beat until everything is well combined.
5. With your mixer on its lowest setting, mix in the flour in three batches with half the milk in between each batch. It's gonna go flour, milk, flour, milk, flour. Mix until just combined.
6. Divide your batter among your 12 waiting cupcake papers. Bake for 20 minutes or until a toothpick comes out clean. Allow the cupcakes to cool in the pan for 10 minutes then transfer to a cooling rack to cool completely before frosting.

For the frosting

1. In a large mixing bowl, beat together the butter and cream cheese until blended. Beat in the powdered sugar. Add it about a half cup at a time if you don't want to clean powdered sugar off every surface of your kitchen. Mix in the vanilla and cinnamon and beat until it's light and fluffy.
2. Spread or pipe your frosting onto your cupcakes. Sprinkle with cinnamon sugar.