In a large mixing bowl, beat the butter with an electric mixer on medium speed until smooth and creamy, about 1-2 minutes.

Add 2 cups powdered sugar, mixing on low.

Add the remaining 2 cups of powdered sugar, heavy cream, vanilla extract, peppermint extract, and salt. Beat on medium-low speed until fully incorporated. If the dough is too dry, add more heavy cream, ½ teaspoon at a time, until it is pliable and holds together when pressed. If the dough is too sticky, add powdered sugar, 1 tablespoon at a time. The dough should feel like playdough.

If using food coloring add 2-3 drops and beat on medium until incorporated. If using more than one color, divide the dough into sections, and beat separately.

On a clean work surface, using extra powdered sugar if needed, roll a portion of dough into a long, thin rope about ½ inch thick. Use a sharp knife or bench scraper to cut the rope into small pieces, about ½ inch long. Repeat with the remaining dough.

Place the mints on a lined baking sheet in a single layer, ensuring they do not touch. Line with parchment paper, wax paper or a silicone mat. Allow the mints to air dry for 12-24 hours. They should be firm but not hard. Store in an airtight container for up to 1 month.