Add vodka and sour mix to a tumbler with ice to chill. Shake ingredients and pour in a large shot glass. Use Grenadine and allow to sink to the bottom of the glass (pour slowly down the inside of the glass. then allow blue curacao to sink to the middle of the glass (it will sit on top of the grenadine if poured slowly down the inside of the glass). the finished product be red, Blue, then white from bottom to top.