Preheat the oven to 350°F (175°C). Line a cake pan with parchment paper or lightly grease it. Grate the carrots using a box grater, aiming for fine shreds, and set aside.
In a large mixing bowl, combine almond flour, cinnamon, nutmeg, baking powder, and salt. Whisk thoroughly until well blended. In a separate medium bowl, beat the eggs until frothy.
Pour the beaten eggs into the dry mixture and stir to combine. Add the grated carrots and chopped walnuts, folding gently until evenly incorporated. The batter should be thick but easily scoopable.
Transfer the batter into the prepared cake pan, spreading it out evenly with a spatula. Smooth the top and tap the pan lightly on the counter to settle the batter.
Bake in the preheated oven for 30-35 minutes, or until the top is golden brown and a toothpick inserted in the center comes out clean. The cake should feel firm and spring back lightly when touched.
Allow the cake to cool in the pan for 10 minutes, then transfer to a wire rack to cool completely. Slice and serve once cooled.
