01 - Preheat oven to 350°F. Grease and line a 9-inch round or square cake pan.
02 - In a large mixing bowl, whisk together the mashed bananas, eggs, vegetable oil, granulated sugar, light brown sugar, and vanilla extract until the mixture is smooth and well combined.
03 - In a separate bowl, whisk together all-purpose flour, baking soda, baking powder, ground cinnamon, and salt until evenly incorporated.
04 - Gradually add the dry ingredients to the wet mixture, stirring with a spatula just until combined. Avoid overmixing for optimal cake texture.
05 - Gently fold in the chopped walnuts, pecans, or chocolate chips, if using.
06 - Pour the batter into the prepared pan and smooth the surface. Bake for 35 to 40 minutes or until a toothpick inserted into the center emerges clean.
07 - Let the cake cool in the pan for 10 minutes, then transfer to a wire rack to cool completely. Serve warm or at room temperature.