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

In a bowl, whisk together the all-purpose flour, baking powder, and salt until well combined. Set aside.

In a separate large bowl, cream together the softened butter, brown sugar, and granulated sugar using an electric mixer until the mixture is light and fluffy.

Beat in the eggs, one at a time, mixing well after each addition. Then, stir in the vanilla extract.

Gradually add the dry ingredients to the butter mixture, alternating with corn syrup until just combined. Fold in the chopped pecans gently to maintain their crunch.

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

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

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

For the frosting, beat together softened butter with brown sugar until smooth.

Gradually add powdered sugar and a splash of milk, mixing until creamy and spreadable.

Once the cupcakes are completely cool, generously frost each cupcake with the brown sugar frosting and top with some extra chopped pecans if desired.