Make the cupcakes based on the directions on the box.
Add one tbsp of peppermint extract to the mix.
Pour the batter into a cupcake tin lined with 12 Christmas cupcake liners and bake for roughly 15 minutes. The instructions on the box say they should bake for 15 to 20 minutes but I recommend checking them after 14 to 15 minutes by inserting a toothpick into the middle. If it comes out clean, the cupcakes are done.
Using a stand mixer, add the frosting and 1 tsp of peppermint extract. Or mix in a bowl. ( Tip: if you like a less strong peppermint flavor, use a bit less or skip it altogether)
Mix the frosting until well combined.
Once the cupcakes are cooled, frost them and decorate them to your liking!
Notes
If your vanilla frosting is a bit crumbly, add some cream cheese or a small splash of nut milk and whisk until smooth.
You can turn the frosting into a chocolate frosting by adding organic unsweetened cocoa powder.
Add the peppermint extract sparingly - depending on the brand, it can be quite potent. You can always add more towards the end if you feel your batter needs it. Should you have added too little extract to the cupcake batter, you can simply add some more to the frosting.
You can obviously use a piping bag to create big swirls of frosting. Or use a large zip-top bag with one corner snipped off.
If you want your cupcakes topped with that signature white and pink swirl of frosting, simply drizzle four drops of all-natural beet food coloring around the inside of your piping bag. Carefully spoon in the prepared vanilla frosting and twist the top of the piping bag shut. As you frost the cupcakes, a pink swirl will appear.