Preheat your oven to 350°F (175°C). Grease and flour a 9x5-inch loaf pan.
In a large mixing bowl, whisk together the flour, sugar, baking powder, salt, nutmeg, and cinnamon until well combined.
In another bowl, mix the eggnog, vegetable oil, eggs, and vanilla extract until smooth.
Pour the wet ingredients into the dry ingredients, stirring just until combined. Be careful not to overmix.
If using, fold in the chopped nuts and raisins or cranberries gently.
Pour the batter into the prepared loaf pan, smoothing the top.
Bake in the preheated oven for 50 minutes or until a toothpick inserted into the center comes out clean.
Let the bread cool in the pan for about 10 minutes before transferring it to a wire rack to cool completely.