Preheat the oven to 350F. Grease a 9x5" loaf pan and set it aside. In a large bowl, whisk together the flour, baking soda, salt, cinnamon, nutmeg, cloves and ginger until combined, then set that aside. In a separate bowl, whisk together the oil, eggs, granulated sugar, brown sugar, milk and pumpkin. Then whisk in the shredded apple and carrot. Pour the wet batter into the dry and fold together until it's just combined, then fold in the walnuts.
Pour the batter into the prepared loaf pan and top with oats if you'd like. Bake for 50-65 minutes, or until a toothpick inserted into the center of the loaf comes out mostly clean. If you notice the bread is browning quickly, then tent some foil loosely over the top halfway through baking time. Let it cool completely in the pan set on a wire rack, before removing the loaf and slicing it. Leftover bread can be stored in the fridge for a week or so.
For Muffins: Grease a 12 count muffin tin instead of a loaf pan and pour the batter to the top of each tin. Initially, preheat the oven to 425F. Bake the muffins for 5 minutes, then keep them in the oven and lower the temperature to 350F and bake for an additional 15-17 minutes, or until a toothpick inserted comes out clean. Let them cool in the pan for 5 or so minutes, then transfer them to a wire rack to cool completely.
For Mini-Loaves (as pictured): Grease the mini-loaf pans rather than the large one. Bake at 350F for 33-38 minutes, or until a toothpick inserted into the centers comes out mostly clean. Place the mini loaf pans onto a wire rack to cool completely.