This layered beer drink made of half stout (generally Guinness) and half pale ale (often Bass) works because the stout is less dense than the ale, so it floats atop the lighter-colored beer, creating a two-tone pint that’s the obvious source of the drink’s name.
The slow pour over the back of a spoon is essential for getting this pint to look just right. You might not nail it on your first try, but as with anything in life, practice makes perfect.
It’s important to note that the name also has political overtones in Ireland and not good ones. The Black and Tans were English paramilitary soldiers who were accused of some of the worst atrocities against the Irish during the Irish War of Independence in the early 1920s; their nickname came from their uniforms, a combination of black and khaki. If you absolutely must satisfy a craving for this drink while in Ireland, requesting a Half & Half at the pub should get you the same drink (or possibly a Harp lager and Guinness, similarly layered) without offending your bartender or fellow patrons.
8 ounces pale ale (such as Bass)
8 ounces stout beer (such as Guinness)
Add the pale ale into a pint glass, filling it halfway.
Very slowly pour the stout over the back of a spoon to fill the glass, floating it on top of the ale for a layered effect.