Easy Sugar Cookie Icing

0 Measure out [wprm-ingredient text="2 ½ cups powdered sugar" uid="0"] into a sifter or a fine mesh strainer.
1 Sift the powdered sugar into a large glass bowl. This sifting will ensure there are no lumps in the sugar. Add [wprm-ingredient text="¼ teaspoon kosher salt" uid="1"], and whisk.
2 In another small bowl, combine [wprm-ingredient text="2 teaspoons pure vanilla extract" uid="2"] with [wprm-ingredient text="⅓ cup milk" uid="3"]. Whisk them together.
3 Pour the wet ingredients into the powdered sugar.
4 Whisk until combined.
5 Measure in [wprm-ingredient text="½ tablespoon freshly squeezed lemon juice" uid="4"], and whisk until smooth. (This will make [adjustable]1 ¼ cups[/adjustable] icing, and it will be relatively thin.)
6 Use a measuring scoop to divide the icing as needed. (For 5 colors, use a ¼ cup measure.)
7 Use [wprm-ingredient text="2-3 drops gel food coloring" uid="5"] of your choice to dye the individual bowls of icing. Stir with a spoon or a knife until the color is correct.
8 Spread the icing thinly on top of the cookies, and let dry for 4-6 hours at room temperature before enjoying.