Preheat your oven to 350°F (175°C). Grease a 9x5-inch loaf pan or line it with parchment paper.

In a large mixing bowl, grate the zucchini, carrot, and apple. Pat the zucchini dry to remove excess moisture.

In another bowl, combine the flour, sugar, baking soda, baking powder, cinnamon, and salt. Stir until well mixed.

In a separate bowl, whisk the eggs together with the vegetable oil and vanilla extract.

Gradually add the wet ingredients to the dry ingredients and mix until just combined.

Gently fold in the grated carrot, zucchini, and apple until evenly distributed throughout the batter.

Pour the batter into the prepared loaf pan, smoothing the top with a spatula.

Place the pan in the preheated oven and bake for about 50-60 minutes, or until a toothpick inserted into the center comes out clean.

Allow the bread to cool in the pan for about 10 minutes before transferring it to a wire rack to cool completely.