1 oz of Cognac
1 oz of Absolut Kurant vodka (or currant-infused vodka)
1 oz of ribena blackcurrant cordial (or blackcurrant cordial)
Pour concentrated Ribena syrup into the test tube first. Then layer the vodka on top of it. Top it off with the cognac. The cognac should stay on top, but some of it will mix with the vodka if you're not careful. Shoot.