Who can resist a fizz? Delightfully frothy, with a crown of foam that feels both indulgent and light, the 19th-century hair-of-the-dog commands the spotlight on any bartop where it appears.

The category’s most popular iteration is the Ramos Gin Fizz, which has been variously compared to “drinking a flower” by one guest (quoted in Famous New Orleans Drinks and How to Mix ’Em) and described as “the most aggravating cocktail in the history of bartending” by Louisiana bartender Mark Schettler, who has spent years perfecting his technique for the cocktail. It’s a crowd-pleaser that takes a bit of work. But not all fizzes—essentially sours turned fizzy and frothy with soda water and an optional egg white—are as demanding as the Ramos, and the approachable template has inspired a range of bartenders to experiment with the format.

Some, like the Mid-Morning Fizz, add complexity to the classic with modifiers like Chartreuse and orange blossom water, while others apply the Mr. Potato Head approach to the drink by swapping out the fizz’s core elements. In the Lefty’s Fizz, from San Francisco bartender Ryan Fitzgerald, smoky mezcal takes the place of gin, complemented by dry Curaçao and a grapefruit shrub for an extra citrus kick. Elsewhere, the Fizz Italiano from Los Angeles’ Lee Zaremba exchanges the template’s typical soda water for a bitter Italian soda, giving it an aperitivo bent.

In fact, the mashup of bitter Italian ingredients with the fizz format seems to be a growing category all on its own, whether the drinks incorporate fernet (like the cola-laced Fernet Ramos from Nashville’s Camille Razo), Campari and Montenegro (like Run the Julius from Columbus, Ohio’s Annie Williams Pierce) or Aperol (like the Phantom Drift from San Francisco’s Alex Smith). 

The evolving family tree of these cocktails is proof that the fizz has lasting appeal, even in its most famously arduous example. “Just go ahead and shake it,” said San Francisco’s Morgan Schick of the manual nature of the Ramos. In the end, it’s worth it: “It’s immensely satisfying to shake and shake and shake, and end up with this beautifully textured drink.”