Begin by softening ½ cup of unsalted butter at room temperature for about 30 minutes. Using a stand mixer or a hand mixer, beat the butter on medium speed until it becomes light and fluffy, which should take about 2-3 minutes.

Gradually add 4 cups of powdered sugar, one cup at a time, to the creamed butter. Mix on low speed to prevent a sugar cloud, then increase to medium speed until the mixture is smooth and well combined.

Pour in 2 tablespoons of heavy cream and 1 teaspoon of peppermint extract, mixing them into the batter. Continue to blend until the mixture is silky and well-combined.

Once fully mixed, assess the dough's texture; it should be smooth and pliable but not sticky. If it feels too soft to handle, cover the bowl with plastic wrap and chill the dough in the refrigerator for 15-20 minutes.

After chilling, divide the dough into smaller sections. Roll each section into a rope shape on parchment paper, aiming for about ½ inch in diameter. Cut the rope into small squares or pieces.

Carefully lay the cut mints in a single layer on a tray, leaving space between each piece. Allow them to air dry at room temperature for at least 12 hours or overnight.

Once dried, transfer the mints to an airtight container. You can layer them with parchment paper to prevent sticking.