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

In a mixing bowl, whisk together the flour, sugar, baking powder, baking soda, and salt.

In another bowl, cream the softened butter until light and fluffy. Add the eggs, vanilla extract, buttermilk, and lemon zest, mixing until well combined.

Gradually add the dry ingredients to the wet ingredients, mixing until just combined. Gently fold in the blueberries.

Divide the batter evenly among the cupcake liners, filling each about two-thirds full.

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

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