‘Tis the season to mix milk into your soda. According to Pepsi, however.

Pepsi launched a Thursday campaign encouraging customers to try the combination and use the hashtag #PilkandCookies (as in Pepsi plus milk) to showcase their Santa-friendly concoctions. Those who participate in the online challenge running through Christmas Day will have the chance to win cash, CNN reported.

“Combining Pepsi and milk has long been a secret hack among Pepsi fans,” said Todd Kaplan, Pepsi’s chief marketing officer, in a statement about the campaign.

Pepsi is now publicizing the mix as its spin on “dirty soda,” a popular TikTok trend that combines soda with syrup and cream. Companies like PepsiCo pay attention to what’s happening on TikTok, and often look for ways to get in on trends as a way to stay relevant to young consumers.

“With the rise of the ‘dirty soda’ trend on TikTok and throughout the country, we thought Pilk and Cookies would be a great way to unapologetically celebrate the holidays,” said Kaplan.

To make the campaign even trendier, Pepsi tapped Lindsay Lohan, star of the Netflix Christmas movie “Falling for Christmas,” to promote the combination.

Pepsi is recommending a number of recipes for those who want to go beyond just Pepsi and milk, perhaps hoping to launch their own viral combination.

A handful of those recipes include the Naughty & Ice, which is Pepsi with one cup of whole milk, one tablespoon of heavy cream and one tablespoon of vanilla cream, plus Pepsi; the