Preheat your oven to 350°F (175°C) and grease the loaf pan.
In a mixing bowl, combine the flour, granulated sugar, baking powder, baking soda, salt, nutmeg, and cinnamon. Whisk together until well blended.
In another bowl, whisk the eggs, eggnog, vegetable oil, and vanilla extract until smooth.
Gradually add the wet ingredients to the dry ingredients, mixing just until combined. Do not overmix. If using, fold in the chopped nuts.
Pour the batter into the prepared loaf pan, spreading it evenly.
Bake in the preheated oven for 55-60 minutes, or until a toothpick inserted in the center comes out clean.
Once baked, remove the bread from the oven and let it cool in the pan for about 10 minutes. Then transfer it to a wire rack to cool completely.
Optionally, dust the cooled bread with powdered sugar before slicing.