Preheat oven to 325 degrees F (165 degrees C). Grease two 9x5-inch loaf pans.
Mix flour, cinnamon, salt, baking soda, baking powder, and nutmeg together in a bowl. Beat sugar, applesauce, eggs, oil, and vanilla extract together in a separate bowl; stir in zucchini. Slowly mix flour mixture into zucchini mixture until well blended; pour into prepared loaf pans.
Bake in the preheated oven until a toothpick inserted in the center comes out clean, about 50 minutes.
