01 - Preheat oven to 350°F. Grease and flour a 9x5-inch loaf pan or line with parchment paper.
02 - In a large bowl, whisk together flour, baking soda, baking powder, salt, cinnamon, nutmeg, and ginger until well blended.
03 - Beat eggs in separate bowl, then add mashed bananas, oil, brown sugar, granulated sugar, and vanilla extract. Mix until fully combined.
04 - Stir grated carrots into the wet ingredients until evenly distributed.
05 - Add wet mixture to dry ingredients. Mix gently until just combined, being careful not to overmix.
06 - Fold in chopped walnuts if using.
07 - Pour batter into prepared loaf pan and spread surface evenly.
08 - Bake for 50-60 minutes until toothpick inserted in center comes out clean.
09 - Let bread cool in pan for 10 minutes, then transfer to wire rack to cool completely before slicing.