Half a pint of Pabst Blue Ribbon with a half pint of Stout or Porter on top; typically Guinness.
I ordered a Black and Tan at the pub. The bartender said she was out of BassAle but they had Pabst Blue Ribbon and Guinness available; So I ordered up Pabst Smear, instead.
When one stands naked head to tails over another and pours a Pabst Blue Ribbon down their back letting it drip down their ass crack and then smearing their backside on their face .