Preheat oven to 350 degrees.
Grease and flour loaf pan.
In a large bowl, combine all dry ingredients- 2 ½ cups all-purpose flour, 1 cup brown sugar, 1 ½ teaspoon baking powder, 1½ teaspoon cinnamon, ¾ teaspoon baking soda, ½ teaspoon nutmeg, ¼ teaspoon ginger, and ¼ teaspoon kosher salt. It is best to use a whisk to aerate the flour.
In a smaller bowl, combine all wet ingredients - 1 can pumpkin puree, ½ cup melted butter, ⅓ cup maple syrup, 2 eggs, 2 teaspoons vanilla extract, and 1 teaspoon orange zest.
Pour the wet ingredients into the dry ingredients and combine with a spatula. Mix just until all dry ingredients have been incorporated.
Spoon into the prepared loaf pan, smoothing the top surface.
Place on a rack in the middle of the oven.
Bake for 1 ½ hours. After 1 ¼ hours, use a skewer to test the doneness of the bread. Insert the skewer in the middle of the bread. If it is clean, the bread is done. If there is batter stuck to the skewer, place the loaf pan back in the oven for the remaining 15 minutes.
Remove the bread from the oven and let cool for approximately 30 minutes. Turn the pan upside down and gently, let the bread slide out of the pan. Place on a rack to continue cooling. The bread is still a little fragile because it is still warm.