for the Cupcakes:

1. Preheat your oven to 350°F (175°C). Line a 12-cup muffin tin with paper cupcake liners.
2. In a medium bowl, whisk together the dry ingredients: flour, baking powder, and salt. Set aside.
3. In a large bowl, cream the butter and sugar together until light and fluffy (about 3 minutes).
4. Add the eggs, one at a time, mixing well after each addition. Stir in the vanilla extract.
5. Gradually add the dry ingredients to the wet ingredients, alternating with the milk. Mix until just combined.
6. Add blue food coloring or butterfly pea flower powder and mix until the batter is a vibrant shade of blue.
7. Divide the batter evenly between the cupcake liners, filling each about 2/3 full.
8. Bake for 18-22 minutes, or until a toothpick inserted into the center comes out clean.
9. Let the cupcakes cool in the tin for 5 minutes, then transfer them to a wire rack to cool completely.

for the Frosting:

1. In a medium bowl, beat the softened butter until creamy and smooth.
2. Gradually add the powdered sugar, one cup at a time, mixing until smooth.
3. Add the heavy cream or milk, one tablespoon at a time, until the frosting reaches your desired consistency.
4. Stir in the vanilla extract and blue food coloring until the frosting is a beautiful shade of blue.
5. Once the cupcakes are completely cooled, frost them with the blue buttercream frosting using a piping bag or a spatula. Optionally, decorate with sprinkles, fresh berries, or any fun toppings you like.