Preheat oven to 350°F (175°C). Line a muffin tin with paper liners.
In a large bowl, whisk together flour, sugar, baking powder, and salt.
In a separate bowl, cream together butter and sugar until light and fluffy. Beat in eggs one at a time, then stir in vanilla.
Gradually add the dry ingredients to the wet ingredients, alternating with the milk, beginning and ending with the dry ingredients. Mix until just combined.
Fill the muffin liners about 2/3 full.
Bake for 15-20 minutes, or until a toothpick inserted into the center comes out clean.
Let cool completely before frosting.
Frost the cupcakes and decorate with pretzels, chocolate chips, and red M&Ms to resemble reindeer.
Notes
These cupcakes are best served fresh. Store leftovers in an airtight container at room temperature.