Prepare: Preheat the oven to 350 degrees Fahrenheit. Line your muffin tins with cupcake liners and set aside

Stir: In a large bowl add the flour, baking soda, baking powder, cinnamon, and salt all at once. Whisk together and then add the white sugar. Mix again until all the dry ingredients are combined.

Combine: Add the buttermilk, oil, and vanilla, to the dry ingredients. Whisk together until a thick batter forms.

Fill muffin pan: Spoon batter into the prepared cupcake liners. Fill muffin cups ¾ way full. Bake in the oven for 20-25 minutes or until a toothpick inserted into the cupcake comes out clean.

Frosting: While the cupcakes are baking, make the cinnamon buttercream frosting. In a medium bowl add the cream cheese and butter, beating with an electric hand mixer until creamy. Add in the powdered sugar and cinnamon. Blend again until combined and thick. Then add the vanilla and milk, a tablespoon at a time. Mix again until smooth and creamy, add as much milk as needed to get a thick, but smooth and pipable consistency. Transfer this into a piping bag fitted with a star metal tip of your choice. Let the cupcakes cool for 30 minutes before frosting.