Preheat oven to 350°F (175°C). Grease a 9×5 inch loaf pan.
In a large bowl, whisk together flour, granulated sugar, brown sugar, baking powder, nutmeg, cinnamon, and salt.
In another bowl, mix together eggnog, vegetable oil, eggs, and vanilla extract.
Add the wet ingredients to the dry ingredients and stir until just combined. Fold in chopped pecans if using.
Pour the batter into the prepared loaf pan.
Bake for 50-60 minutes, or until a toothpick inserted into the center comes out clean.
Allow to cool in the pan for 10 minutes, then transfer to a wire rack to cool completely