By An Edible Mosaic
Pro tip
Add the butter, sour cream, and vanilla to a large bowl and cream together until smooth (you use a handheld electric mixer or do this by hand). Add the powdered sugar, flour, and salt, and stir to combine.
Immediately transfer the dough to a piping bag fitted with a large star tip. Pipe the dough out into round circles onto the baking tray, leaving about 2 inches between each cookie.
Bake until the cookies are light golden on the bottom, about 10 to 15 minutes. Cool on the baking tray and then remove with a thin metal spatula.