01 - Preheat your oven to 350°F. Line two 12-cup muffin pans with cupcake liners.
02 - In a bowl, whisk together flour, baking powder, baking soda, and salt until well combined.
03 - In a large bowl, cream butter and sugar until light and fluffy. Beat in eggs one at a time, then add vanilla.
04 - Add the dry ingredients in three parts, alternating with milk, beginning and ending with the flour mixture. Mix until just combined.
05 - Divide batter evenly among liners, filling about 2/3 full. Bake for 18–20 minutes or until a toothpick inserted comes out clean. Cool completely on a wire rack.
06 - Beat butter until creamy. Gradually add powdered sugar, then vanilla and milk as needed for desired consistency. Tint with green gel food coloring.
07 - Once cupcakes are completely cool, pipe buttercream in a tall swirl on each cupcake using a large star tip.
08 - Arrange cupcakes in a tree shape on a large board or platter: start with 7 cupcakes at the base, then 6, 5, 4, and finish with 2 and 1 at the top to form a triangle.
09 - Decorate with sprinkles as ornaments. Place the gold star topper at the peak. Add candy canes, pearls, or coconut for extra decoration if desired.