Preheat your oven to 350°F (175°C) and line a 12-cup muffin tin with cupcake liners.

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

Add the eggs one at a time, mixing well after each addition. Stir in the vanilla extract.

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

Gradually add the dry ingredients to the butter mixture, alternating with the buttermilk, starting and ending with the flour mixture.

Gently fold in the diced strawberries and mango until evenly distributed.

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 the cupcakes to cool in the pan for 5 minutes before transferring them to a wire rack to cool completely.

For the frosting, beat the softened butter in a bowl until creamy.

Gradually add the powdered sugar, mixing on low speed until combined.

Add the heavy cream, vanilla extract, and pureed strawberries, then beat on high speed until the frosting is light and fluffy.

Once the cupcakes are completely cool, frost them generously with the strawberry frosting. Decorate with additional diced strawberries or mango if desired.