French 75

Have one on me. It worked for Bob & Norma in Riptide:

French 75

* 1 ounces gin
* 1/4 ounce lemon juice
* 1/8 ounce simple syrup
* 5 ounces chilled champagne

Shake gin, lemon juice, and syrup with ice. Strain into a champagne flute. Top with champagne.