Preheat the oven to 350F. Prepare a 9" spring form cake pan with parchment paper.
In a small bowl, whisk together the flour, baking powder, spices and salt.
In a larger bowl, whisk together the carrots, eggs, pistachio butter, and honey
Gradually pour the dry ingredients into the wet and mix to combine.
Pour the batter into the cake pan and bake at 350F for 22-26 minutes or until you can insert a toothpick and it comes out clean.
While the cake is baking, you can prepare the icing. Add the cream cheese to a stand mixer, or use an electric mixer. Mix for about a minute on medium or until the cream cheese is smooth. Add the butter and mix for another minute, then gradually sift in the powdered sugar. Continuing mixing until no clumps remain. Taste and add sugar as you see fit!
Let the cake cool completely before putting on any icing. Add a generous layer of icing to the top, and serve whenever!