Add two sticks of softened butter to a large bowl.
Add 1½ pounds of sifted confectioners sugar to the butter along with 2 teaspoons of fresh lemon zest, ½ teaspoon pure vanilla extract, and 2 teaspoons ginger paste.
Blend until smooth.
Add 1 teaspoon fresh lemon juice along with 2-3 tablespoons of milk (or half and half), depending on your desired consistency.
Add the lemon ginger buttercream frosting to a piping bag and pipe onto cake or cookies.