Preheat oven to 350°F (175°C) and grease your cake pan.
Mix dry ingredients: In a large bowl, whisk together almond flour, coconut flour, sweetener, baking powder, baking soda, salt, cinnamon, and nutmeg.
Mix wet ingredients: In another bowl, beat the eggs, almond milk, coconut oil, and vanilla extract until smooth.
Combine the wet and dry ingredients, stirring until fully mixed.
Fold in grated carrots and nuts (if using).
Pour batter into the greased pan and smooth the top with a spatula.
Bake for 30–35 minutes or until a toothpick comes out clean.
Cool in the pan for 10 minutes, then transfer to a rack to cool completely.
Prepare frosting: Beat cream cheese and butter until smooth. Add sweetener, vanilla, and heavy cream, and beat until creamy.
Frost the cake once it has fully cooled. Serve and enjoy!