Preheat the oven to 350°F (175°C). Grease and flour your cake pan or line it with parchment paper.
In a large bowl whisk together the dry ingredients: All-Purpose Flour, Baking Soda, Baking Powder, Salt and Ground Cinnamon until evenly combined.
In a separate bowl beat together Granulated Sugar, Vegetable Oil, Eggs and Vanilla Extract until smooth and slightly pale. Stir in the grated Carrots.
Pour the wet mixture into the dry ingredients and fold gently until just combined—do not overmix. Fold in the chopped Walnuts.
Transfer the batter to the prepared pan and smooth the top. Bake for 25–35 minutes, or until a toothpick inserted into the center comes out clean. Let the cake cool in the pan for about 10 minutes, then turn out onto a wire rack to cool completely.
For the frosting, beat softened Cream Cheese and softened Butter together until smooth and creamy. Gradually add Powdered Sugar and beat until light and fluffy, then stir in a splash of vanilla extract to taste.
Once the cake is completely cool, spread the cream cheese frosting over the top (and sides, if desired). Sprinkle extra chopped walnuts on top for garnish, slice, and serve.
