Preheat the oven to 375°F.

In a medium-sized mixing bowl, mix butter and white sugar.

Add the egg and continue to mix until combined.

Stir in the peppermint extract.

Combine flour and baking powder and add it in batches to the wet ingredients until fully mixed.

Using a 2 teaspoons cookie scoop, scoop the dough and shape into a ball using your hands.

Place onto a parchment paper-lined cookie sheet and flatten just a little.

Bake for 8 minutes then remove from oven.

After a few minutes, transfer to a wire cooling rack. Cookies will need to be completely cooled before frosting.

While the cookies are cooling you can make the frosting by adding to a medium bowl the powdered sugar, melted butter, heavy cream and peppermint extract.

Beat the mixture until thick and smooth. The frosting should be spreadable but should hold its shape when added to the cookies. You can add a little extra heavy cream (1 teaspoon at a time) if too thick, or extra powdered sugar (1-2 tablespoons at a time) if too thin.

Frost each cookie and sprinkle with the crushed peppermint candy for garnish before plating and serving.