01 - Preheat oven to 350°F. Grease and flour a 9x5-inch loaf pan or line with parchment paper.
02 - Whisk together flour, baking soda, baking powder, salt, cinnamon, nutmeg, and ginger in a large bowl.
03 - Beat eggs in a separate bowl. Add mashed bananas, oil, brown sugar, granulated sugar, and vanilla extract. Mix until well combined.
04 - Stir grated carrots into the wet mixture until evenly distributed.
05 - Pour wet ingredients into dry ingredients. Mix gently until just combined. Do not overmix.
06 - Fold in chopped walnuts if desired.
07 - Pour batter into prepared loaf pan and spread surface evenly.
08 - Bake for 50 to 60 minutes until a 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.