For the cupcakes - Preheat oven to 350°F (180°C). Line a cupcake pan with paper liners; set aside.
In a medium mixing bowl, whisk the flour, baking soda, and salt; set aside.
In a large mixing bowl, cream the sugar and butter together on medium-high speed until light and fluffy. Add in the eggs, mashed banana, and buttermilk and continue to beat until combined.
Mix the dry ingredients into the wet ingredients just till combined.
Divide the batter evenly among the liners, filling 2/3 full (about 1/4 cup of batter per cupcake).
Bake for 23-25 minutes until a toothpick comes out clean.