In a large bowl, combine flour, baking powder, baking soda, salt, and sugar. In a separate bowl, whisk mashed banana, oil, egg, and buttermilk until smooth. Gently fold flour mixture into liquid until just combined. Set batter aside for a moment, while you prepare the cinnamon swirl.

In a small bowl, whisk all swirl ingredients until thick and smooth. Transfer mixture to a small ziplock bag. Seal and cut off one of the corners.

Heat a greased nonstick skillet to medium-high heat. Drop prepared pancake batter by 1/4 cupfuls onto hot griddle. Carefully squeeze cinnamon swirl in a swirl shape on top of pancakes within 1/4-in of the edges. Flip pancakes and cook on opposite side 1-2 minutes or until golden. Repeat cooking procedure with remaining pancake batter and cinnamon swirl. Enjoy pancakes warm with plenty of maple syrup!