Preheat the oven to 350°F (175°C) and line a muffin tin with cupcake liners.

In a mixing bowl, cream together the softened butter and granulated sugar until light and fluffy.

Add the eggs, lemon zest, and lemon juice, mixing until well combined.

In another bowl, whisk together the flour, baking powder, baking soda, and salt.

Gradually add the dry ingredients to the wet ingredients, alternating with the milk, until just combined.

Gently fold in the blueberries.

Scoop the batter into the prepared muffin tin, filling each liner about 2/3 full.

Bake for 18-20 minutes, or until a toothpick inserted into the center comes out clean.

Allow to cool in the tin for 5 minutes before transferring to a wire rack to cool completely.

In a mixing bowl, beat the softened butter until creamy.

Gradually add the powdered sugar, lemon juice, and lemon zest, mixing until smooth and fluffy.

If the frosting is too thick, add a tablespoon of milk to reach desired consistency.

Once the cupcakes are completely cool, frost them with the lemon frosting using a piping bag or a spatula.

Optional: Garnish with additional blueberries or lemon zest on top.