3/4 pint Guinness® stout
1/2 shot Bailey's® Irish cream
1/2 shot Jameson® Irish whiskey
Add the Bailey's and Jameson to a shot glass, layering the Bailey's on the bottom. Pour the Guinness into a pint glass or beer mug 3/4 of the way full and let settle. Drop the shot glass into the Guinness and chug. If you don't drink it fast enough it will curdle and increasingly taste worse.