Preheat the oven to 325 degrees.
In the bowl of an electric mixer, add the ½ cup salted butter and 1 cup granulated sugar and beat on medium-high speed until light and fluffy, about 4 minutes.
½ cup salted butter, 1 cup granulated sugar
Add the 1 egg and 1 tsp vanilla extract and mix until combined. Add the ⅔ cup whole milk and 2 tbsp chai tea concentrate and stir until combined.
1 egg, 1 tsp vanilla extract, 2 tbsp chai tea concentrate, ⅔ cup whole milk
In a small bowl, whisk together the 1 ½ cups cake flour, 1 ½ tsp baking powder, ½ tbsp chai tea, and 1 tsp cinnamon. Add the dry ingredients to the mixer and mix on medium speed for about 2 minutes until a smooth batter forms.
1 ½ cups cake flour, ½ tbsp chai tea, 1 tsp cinnamon, 1 ½ tsp baking powder
Line a muffin tin with paper liners and use an ice cream scoop to fill them 3/4 full with batter.
Bake for 15 minutes until a toothpick comes out clean.
In the bowl of an electric mixture, start the frosting by beating the 1 cup salted butter on high speed for 5 minutes. Add the 2 ½ cups powdered sugar, ½ tbsp chai tea, and 2 tsp cinnamon and beat on medium speed for an addition 5 minutes until the frosting is light and fluffy and has increased in volume.
1 cup salted butter, 2 ½ cups powdered sugar, ½ tbsp chai tea, 2 tsp cinnamon
Fill a piping bag fitted with a 1 inch round tip. Pipe a round of frosting onto the cooled cupcakes and dip into the ½ cup cinnamon sugar until coated. Pipe an additional swirl of frosting on top of the cupcake as shown in the picture. Sprinkle lightly with cinnamon and serve.
½ cup cinnamon sugar