In a blender, combine the vanilla ice cream, milk, peppermint extract, crushed peppermint candies, chocolate chips, and red food coloring (if using).
4 cups vanilla ice cream, 1/3 cup milk whole or 2% milk, ¼ teaspoon peppermint extract, ⅓ cup crushed peppermint candies, ¼ cup chocolate chips, 2-3 drops of red food coloring