|1||oz||Rye, Rittenhouse 100|
|2||oz||Grapefruit juice (pink)|
|1||oz||Lillet Rouge (or Carpano Antica; as float)|
|2||ds||Grapefruit bitters (as float)|
Shake, strain over rocks in a highball, top with fortified wine and bitters.
Maggie Hoffman of Serious Eats recommends Carpano Antica Formula vermouth in place of the Lillet Rouge. You could also try Dubonnet, Byrrh, Bonal, etc.