Preheat the oven to 375°F. Line a muffin pan with cupcakes liners and set aside. Since this recipe yields 16 muffins, I use one 12 muffins pan and one 6 muffins pan (with 4 liners).
In a medium size mixing bowl, whisk together 2 cups whole wheat flour, 1 tsp baking powder, 1 tsp baking soda, ½ tsp cinnamon, and ¼ tsp salt, and set aside.
In a large mixing bowl, add wet ingredients: ½ cup vegetable oil, ¼ cup apple sauce, ⅔ cup maple syrup, 3 eggs, orange zest, ¼ cup orange juice, and 1 tsp vanilla extract. Whisk until well combined.
Add dry ingredients to wet ingredients, and using a spatula, fold it in. Try not to over mix the batter.
Add 2 cups grated carrots, 1 cup grated apple, ⅔ cup raisins, and ⅔ cup chopped walnuts. Fold everything in. Again, try not to over mix.
Using a 3 tablespoons ice scream scoop, divide the batter between 16 muffin liners, filling then all the way to the top.
Bake at 375°F for 20-25 minutes, or until a toothpick inserted in the center comes out clean.
Take them out of the oven and let sit on the counter for 5-7 minutes in a muffin pan, then transfer to a wire rack to cool off completely.