Preheat the oven to 350ºF and line a 8x8 baking tray with parchment paper.
In a small bowl, combine the apple cider vinegar and non dairy milk. Set aside to curdle.
1 ¼ cup non dairy milk, 1 tsp apple cider vinegar
In large bowl, whisk together the flour, salt, baking powder and cinnamon.
2 cups all purpose flour, ½ tbsp baking powder, ½ tsp salt, 1 tsp ground cinnamon
Add the curdled milk, oil, brown sugar and shredded carrot to the bowl of dry ingredients. Use a spatula or wooden spoon to mix everything until a smooth batter forms. Fold in the crushed walnuts.
½ cup brown sugar, ¼ cup vegetable oil, 1 cup peeled and shredded carrot, ¼ cup crushed walnuts
Pour the batter into baking tray. Use a spatula to evenly distribute the batter and cover the pan. Bake for 20-25mins, or until a toothpick inserted in the middle comes out clean. Carefully transfer to a cooling rack to cool completely before frosting.