Make the Macaron Shells:

1. Prepare Dry Ingredients: Sift the powdered sugar and almond flour together into a large bowl. Discard any large pieces.
2. Whip Egg Whites: In a separate clean bowl, beat egg whites on medium speed until foamy. Slowly add granulated sugar and continue whipping until stiff peaks form.
3. Flavor & Color: Add vanilla extract, peppermint extract, and a small amount of red gel food coloring. Gently fold until combined.
4. Macaronage Process: Fold the dry ingredients into the egg white mixture using a spatula. Continue folding until the batter flows like lava and forms a ribbon when lifted.
5. Pipe the Macarons: Transfer the batter to a piping bag fitted with a round tip. Pipe small circles onto a baking sheet lined with parchment paper or a silicone mat. Tap the tray firmly to release air bubbles.
6. Rest the Macarons: Let them sit at room temperature for 30-60 minutes, or until a skin forms on top and they are no longer sticky to the touch.
7. Bake: Preheat oven to 300°F (150°C). Bake for 12-14 minutes, until set. Let cool completely before filling.

Make the Buttercream Filling:

8. Beat the Butter: In a bowl, beat softened butter until smooth.
9. Add Sugar & Peppermint: Slowly mix in powdered sugar and peppermint extract. Add heavy cream as needed for consistency. Beat until fluffy.
10. Fill Macarons: Transfer the buttercream to a piping bag. Pipe a small amount onto one macaron shell and sandwich with another.
11. Decorate (Optional): Roll edges in crushed peppermint candies or drizzle with melted chocolate.