For the Super Soft Cupcakes:
Get Set: Preheat your oven to 350°F (176°C). Line a 12-cup muffin pan with festive cupcake liners.
Combine Dry: In a medium bowl, whisk together the flour, baking powder, nutmeg, and salt. Set this aside for a moment.
Cream Wet Goodness: In a large mixer bowl, beat the room temperature butter, sugar, and vegetable oil until the mixture is beautifully light in color and fluffy, about 3 minutes. This creaming step is key for tenderness!
Add Eggs & Vanilla: Beat in the eggs one at a time, mixing just until combined after each. Add the vanilla extract with the second egg. Don't forget to scrape down the sides of the bowl to ensure everything mixes perfectly.
Alternate Mixing: Gently mix in half of your dry ingredient blend until mostly combined.
Stir in Eggnog: Slowly pour in the eggnog, mixing until it's well incorporated into the batter.
Finish Mixing: Add the remaining dry ingredients and mix just until the batter is smooth. Remember, avoid over-mixing to keep your cupcakes light and fluffy!
Bake to Perfection: Fill each cupcake liner a little over halfway. Bake for 15-18 minutes, or until a toothpick inserted into the center comes out clean.
Cool Completely: Remove the baked cupcakes from the oven and transfer them to a wire rack to cool down completely before frosting.
For the Luscious Eggnog Buttercream:
Whip Fats: In a large mixer bowl, combine the softened butter and shortening (or your preferred fat) and mix until well blended.
Sweeten It Up (Part 1): Add 2 cups of powdered sugar and mix until smooth.
Infuse Flavor: Stir in 2 tablespoons of eggnog, the optional rum extract, nutmeg, and a pinch of salt. Mix until beautifully smooth.
Sweeten It Up (Part 2): Add the remaining powdered sugar and mix until your buttercream is silky smooth.
Final Creaminess: Pour in the rest of the eggnog and mix until the frosting is wonderfully light, smooth, and perfectly combined.
Frost & Garnish: Generously frost your completely cooled cupcakes. For a charming finish, sprinkle with a little extra nutmeg!