CHICAGO – The quest to shake up McDonald's menu is boldly going places no fast-food aficionado dared dream: a Chocolate Shamrock Shake.

The seasonal, mint-flavored green shake will still be available, but four new varieties also are rolling out this year, including a hybrid that's half chocolate, half Shamrock and all about menu disruption.

Other new offerings include the Shamrock Chocolate Chip Frappe, Shamrock Mocha and Shamrock Hot Chocolate.

"McDonald's is on a journey to be better and part of that journey is a commitment to evolving our food and beverage offerings," Jeanette DeBartolo, a McDonald's spokeswoman, wrote in an email Friday. "McDonald's changes have touched our food and restaurant experience to better meet the changing needs of our customers."

McDonald's last month launched the Grand Mac and Mac Jr., a bigger and a smaller version of the Big Mac, its classic 50-year-old double-decker hamburger with signature "special sauce."

The Shamrock Shake — vanilla soft serve blended with mint syrup — has its own venerable history, and something of a cult following. Launched in 1970, the distinctive green shake is available only in the weeks leading up to St. Patrick's Day. The shakes will be available this year beginning Feb. 7.

McDonald's is doing more than tweaking its menu in a bid to transform itself into a more modern and progressive company. The world's largest hamburger chain is moving in spring 2018 from its longtime headquarters in suburban Chicago into a new nine-story building going up at the site of Oprah Winfrey's former Harpo Studios in Chicago's trendy West Town neighborhood.