The following is based on the Silver Fizz; and it does double duty by mixing the Cel-Ray soda with another New York classic the egg cream.
2 oz. Gin or Bols Genever
1 Egg White
1 Teaspoon Sugar*
2 Dashes Grapefruit Bitters
Cel-Ray Soda to fill
Combine gin, egg white and bitters in a shaker over ice. Strain into a chilled high ball glass. Fill with Cel-Ray Soda, add sugar and give a quick stir. Garnish with a lemon twist and a thin very piece of a celery stalk.
*Adding the sugar last will give you a foam stiff enough to hold a penny. But, the Cel-Ray is pretty sweet on it’s own, so the sugar is optional. If you really want the foam but want to keep it from being cloying you can replace the Cel-Ray with Seltzer and add some celery bitters; but you kind of tear the heart out of the thing.