Say goodbye to the drinker’s golden rule, “Beer before liquor, never been sicker.” A new style of mixing the two favored forms of alcohol is emerging with frothy force in L.A.'s increasingly sensual drinkscape: the beer cocktail. Novel mixtures of beer, gin, vodka, whiskey, juices, infusions and herbs, beer cocktails are pouring two of the city’s most hedonistic obsessions — craft beer and mixology — into a single glass, one that showcases the properties of fine beer rather than shunting it to the side as just another ingredient.

Look closely at the drink menus of the city’s finest bars and you’ll likely see a beer cocktail peering back at you. Matthew Biancaniello at the Library Bar in the Hollywood Roosevelt hotel infuses gin with Cascade hops and mixes it with IPA, grapefruit juice, lemon and honey; upstairs at the Spare Room, Naomi Schimek makes a winter drink called the Robert Frost with apple juice, Amaretto, lemon juice and Magic Hat No. 9. Jonathan Kleinbart (part of Julian Cox’s bar program) has a drink on Playa’s menu made with Port Brewing’s Old Viscosity, Cognac, egg yolk, honey and sherry. Brady Weise makes one with vodka, Yeti stout and crème de cacao at 1886 in Pasadena, and Aidan Demarest features another at Neat in Glendale with Old Rasputin stout, gin, egg, ginger beer and Tabasco.

The list goes on and on: Church & State, Eva Restaurant, Steingarten LA, the new (unfortunately named) German restaurant Wolfslair Biergarten in Hollywood, the Tripel in Playa Del Rey, Ammo, Haven Gastropub in Pasadena, Sadie, Hemingway’s Lounge in Hollywood, the Varnish, the Edison and many more have all featured or feature them.

“I think that a majority of this is coming from the huge spike in the popularity of craft beer in L.A. in general over the past few years,” says Dave Watrous, a bona fide beer guy and the beverage director at Steingarten LA, which hosted an L.A. Beer Week event in October featuring a slew of decadent beer cocktails created by the Library Bar’s Biancaniello. The event, a huge success, showcased a super-rare distilled Belgian lambic beer mixed with white balsamic, strawberries, basil and elderflower liqueur, alongside five other options including an Upside Down Deconstructed Umami Milkshake in 2 Stages that mingled a mushroom-infused bourbon ice cream with Belgian tripel reduction and coffee-infused artichoke liqueur.

Yes, that’s a mouthful, but the name of the game, say beer cocktail proponents, is mouthfeel. That and the way beer can round out and soften the harsher notes in hard liquor without watering it down with bubbly staples such as club soda.

“We’re in an age right now where mixology has taken off so much that people will think that anything is possible in a cocktail,” says Biancaniello, who this weekend plans to infuse a batch of tequila with hops and add beer and fresh Sriracha hot sauce from the farmers market to create “a fully alcoholic michelada.”

The Mexican michelada (a combination of beer, tomato juice, hot sauce and lime juice) is an early progenitor of today’s beer cocktails, as is the Irish car bomb, which calls for a shot of whiskey to be dropped into a glass of beer, and the shandy, which mixes beer and soda or cider.

Similarly, Demarest first harnessed the power of beer at the Edison four years ago when he hit on the idea of using light beer in lieu of Champagne in Champagne cocktails.

“It was my quest to eliminate sugar from Champagne cocktails,” says Demarest, who has asked Weise to host a night of beer cocktails at Neat on March 6. “You get the same mouth feel of bubbles and flavor — beer is a great, savory way to do that. Our customers drank ‘em like crazy.”

Neat is just down the road from L.A.'s newest and most ambitious brewery, Golden Road Brewing, and not far from Eagle Rock Brewery, both of which, says Weise, are pushing boundaries when it comes to craft beer by aging it in wine and oak casks to enhance the profile of the malt and hops. This in turn can enhance the flavor of a fine craft liquor, and Weise has approached both breweries about the possibility of creating small-batch runs of specialty beers just for cocktails. Nothing has been agreed upon yet, but the brewers are excited by the possibilities.

“There are so many seasonal craft beers with so many different flavor profiles that you can mix and match them to create a completely different flavor experience based on a single cocktail,” says Weise, who got serious about beer cocktails after replacing the orange peel in a Negroni, a drink that calls for citrus, with Hefeweizen, which has citrus notes. “It’s what [noted mixologists] Marcos Tello and Eric Alperin like to call an ‘evolving cocktail.’”

But have drinkers really been able to get past the adage about not mixing their beer and liquor?

“It’s not counterintuitive at all,” says Watrous. “It’s a natural progression. It’s added a fresh element to cocktails and opened a new window on beer.”

jessica.gelt@latimes.com