Whisk soy milk and ground flax together in a small bowl. Set aside for 5 minutes.
Preheat oven to 350°F/180°C**1.Line a loaf pan with parchment paper.
In a large bowl, combine the wet ingredients (carrots, applesauce, peanut butter, brown sugar, vinegar, vanilla extract, and flax mixture).
Sift whole wheat flour, baking soda, cinnamon, and nutmeg on top of the wet ingredients. Fold the batter together until just combined.
Add walnuts and raisins and fold into the batter a few times to distribute.
Pour the batter into the prepared loaf pan. Bake for 60-75 minutes, until a toothpick inserted in the center of the loaf comes out clean. (A 9x5-inch pan should take about 60 minutes. An 8x4-inch loaf pan can take up to 75 or even 90 minutes. See notes for mini loaves**1.)
Place the loaf pan on a wire rack. Cool for 10 minutes, then gently lift the loaf out of the pan. Place the loaf on the wire rack and carefully remove the parchment paper. Let the bread cool completely before slicing.
Store leftovers in an airtight container at room temperature for up to 48 hours or in the fridge for up to a week. To freeze, cut into slices first, then freeze for up to two months.
Notes
Mini Loaves: I've made this carrot bread into mini loaves using 5.5x3-inch pans. It will make three mini loaves. Bake at 325°F/160°C for about one hour. Try not to tent with foil as I've noticed this can cause mini loaves to sink.