Place the butter, confectioner’s sugar and vanilla in a large bowl, and beat with an electric mixer until it looks combined, light, and fluffy. Add the flour and salt, and mix until it’s crumbly and looks like it can’t be mixed more. Add the milk, then keep mixing, and the dough should clump together after about 15 seconds of mixing.
Place the dough into a pastry bag fitted with a large star tip(1M Wilton), and pipe onto a silicone mat lined baking sheet.
Bake the cookies for 12-15 minutes or until lightly golden.