• About an hour before you begin, put the orange juice in a bowl and soak the raisins.
• Preheat oven to 350°. Grease two 8x2 inch round cake pans. If you want, you can line the bottoms with rounds of parchment and grease parchment. I do this just for extra insurance in case the cakes are sticky.
• Whisk the buckwheat flour, almond flour, brown sugar, baking soda, baking powder salt and spices together and set aside.
• In another bowl, beat the eggs with an electric mixer or whisk, and stream in the oil gradually so that it will emulsify. Add the vanilla. Mix together the egg mixture and the flour mixture, then stir in the carrots and the undrained raisins (which most likely have absorbed all of the juice). Add the nuts if using.
• Divide the batter between the two pans and bake in the pan and bake at 350° for about 30 minutes or until a wooden pick inserted in center comes out clean. Let cool, then frost with cream cheese frosting.

Frosting

• Beat the softened cream cheese and butter in a stand mixer bowl until light and fluffy. Add powdered sugar and beat at low speed until well blended. Beat in vanilla and maple syrup, scraping the bowl often. If your icing is runny from the syrup you can chill it for 30 minutes, but it should be spreadable right away.
• Place 1 cake layer on platter. Spread with about a cup of the frosting Top with second layer. Spread remaining icing over entire cake. Arrange pecan halves or walnuts pieces on top. Cover the cake with a cake dome and keep the whole covered cake in the refrigerator or leave it out for a few hours depending on the temperature in your kitchen.