Preheat the oven to 350 F. Line a 12-cup muffin pan with cupcake liners, then lightly spray the inside of the liners with baking spray.
In a large mixing bowl, whisk the flour, sugar, baking powder, salt, cinnamon, and nutmeg together until well combined. Set aside.
In a separate large mixing bowl, whisk the melted butter, oil, eggs, sour cream, eggnog, and vanilla together until smooth and creamy.
Pour the wet ingredients into the bowl of dry ingredients and whisk to combine.
Scoop cupcake batter into each cupcake liner, filling each one about ⅔ full. Bake cupcakes at 350 F for 17-20 minutes, or until a toothpick inserted into the center of a cupcake comes out clean.
Allow the cupcakes to cool for five minutes in the muffin pan, then carefully remove them from the pan and transfer them to a wire baking racks to finish cooling.
Top the cupcakes with your favorite frosting and holiday sprinkles.