Preheat oven to 350°F and adjust oven rack to center position. Grease a 9x5" loaf pan very well and set aside.
In a large bowl, whisk flour, baking soda, baking powder, salt, brown sugar, cinnamon, nutmeg and cloves very well. Set aside.
In a separate bowl, whisk all wet ingredients until smooth. Make a well in the center of dry ingredients and pour in the wet. Mix very well until everything is just combined. Fold in chopped walnuts. Don't over-mix. Pour batter into prepared loaf pan.
Bake for 45-50 minutes or until a toothpick inserted in the center comes out with a few moist crumbs. Do not over-bake or you will have a very dry, crumbly bread! At about 30-35 minutes you will want to cover the bread loosely with a piece of foil so the top doesn't get too dark.
While bread is cooling, prepare cream cheese frosting. In a large bowl, beat butter and cream cheese until smooth with no lumps. Mix in powdered sugar and vanilla extract until creamy and smooth. If you want a thinner frosting, add some heavy cream (or milk) a little bit at a time until desired consistency is achieved.