Begin by placing your room-temperature unsalted butter into a large mixing bowl. Use a hand mixer or stand mixer on medium speed to beat the butter until it becomes smooth and creamy, which should take about 2-3 minutes.

Next, add in the peppermint extract, a pinch of salt, and your choice of heavy cream or milk. Mix them all together until fully incorporated, which will take another minute.

Gradually sift in the powdered sugar while mixing on low speed to prevent a sugary cloud! Continue to mix until the ingredients come together into a soft, pliable dough. This process may take about 3-4 minutes.

If you'd like to add a touch of pastel color, divide your dough into equal portions. Using gel food coloring, knead in a small amount at a time until you achieve your desired hue. Ensure the color is evenly distributed throughout the dough, which may take about 3-5 minutes of kneading.

Dust your clean work surface with powdered sugar to prevent sticking. Take portions of the dough and roll them into ropes approximately 1/2 inch thick. Using a sharp knife, cut the ropes into bite-sized pieces, about 1 inch long.

Place the shaped mints in a single layer on parchment paper. Leave them to air dry at room temperature for at least 8 hours or overnight.