Preheat the oven to 350F and grease and line a 9x5 inch loaf pan. Stir the milk and vinegar together and let sit for 5 minutes.
In a medium bowl, whisk together the flour, baking soda, baking powder, salt, cinnamon, nutmeg, and cloves.
In a large bowl, whisk the pumpkin puree, granulated sugar, brown sugar, oil, vanilla, and the milk mixture until smooth.
Fold the dry ingredients into the wet just until no streaks of flour remain - overmixing makes the bread tough.
Pour into the pan and bake for 55-65 minutes, until a toothpick comes out with just a few moist crumbs. Tent with foil after 40 minutes if the top browns too fast.
Cool in the pan for 15 minutes, then transfer to a rack to cool completely. The flavor gets even better the next day, wrapped and stored at room temperature.
