Preheat oven to 350 degrees F.
Grease and flour two 9x5 bread loaf pans.
Thoroughly mix flour, cinnamon, baking powder, baking soda, salt, cloves, ginger, and nutmeg in a large bowl. Stir in the walnuts.
In a separate bowl, whisk oil, beaten eggs, vanilla, and both sugars.
Whisk in the persimmon pulp.
Add the dry ingredients to the persimmon mixture. Mix gently until combined.
Pour batter into prepared loaf pans. Decorate with slices of persimmons, if desired. Bake for one hour, or until a toothpick inserted into the center comes out clean