- Preheat your oven to 325°F. 
- Grease two 5-by-9-inch loaf pans with cooking spray or line them with parchment paper. 
- In a large mixing bowl, sift together the flour, baking soda, baking powder, cinnamon, and salt. 
- In another bowl, beat the eggs. 
- Add the vegetable oil, vanilla extract, sugar, and brown sugar. 
- Mix thoroughly until well combined. 
- Slowly fold the wet ingredients into the dry mixture until just blended. 
- Don’t overmix to keep the bread light. 
- Fold in the grated zucchini and chopped nuts (if using), ensuring even distribution without overmixing. 
- Pour the batter into the prepared loaf pans. 
- Spread the batter evenly with a spatula. 
- Bake for 50-60 minutes or until a toothpick inserted in the center comes out clean. 
- Let the bread cool in the pans for 10 minutes, then transfer to a wire rack to cool completely.