Preheat oven to 350°F and grease and flour standard size (8 1/2 x 4 1/2 x 2 1/2 inch) loaf pan.
In a medium-sized bowl, add flours, baking soda, baking powder, salt, cinnamon, nutmeg, cloves and mace and mix together with a whisk. Set aside.
In a stand mixer fitted with the paddle attachment or with a hand-held mixer add eggs and blend on medium speed until well mixed. Add vanilla. With mixer running on medium speed, slowly pour extra virgin olive oil in a steady stream into the bowl until fully incorporated with the eggs and vanilla.
Add sugars, mashed sweet potato, orange zest and milk and mix until combined.
Add dry ingredients all at once and mix just until combined. Do not over mix.
Add chopped pecans and fold into batter by hand.
Pour batter into prepared loaf pan and place into preheated oven for 55 minutes to 1 hour. The loaf is done when a wooden skewer is inserted and removed and a few crumbs remain.
Cool loaf in pan for 10 minutes before removing to cooling rack. Loaf must be completely cooled before icing.
Makes 1 loaf.
Orange Icing
Mix all ingredients together with a wooden spoon and pour over loaf. Icing will be thick.