Preheat the oven to 300°F. Spray a 9 x 13 x 2-inch pan with cooking spray.

In a large mixing bowl, thoroughly blend the butter, honey, and eggs.

In another bowl, combine both flours, the baking soda, and cinnamon. Sift 1½ cups of the flour mixture over the egg mixture.

Stir, then add the remaining sifted flour mixture and stir until well blended. Fold in the carrots, and nuts (if using.)

Spread the batter in the prepared pan and bake for about 45 minutes, or until a toothpick inserted near the center comes out clean.

Remove the cake from the oven and cool on a wire rack before frosting. Top with cinnamon.