To get a free taco, all you have to do is order online, through their app, or in-store from 8-11:59 p.m. local time.
McDonald's said they are offering the McFlurry for free as an apology for its confusing straw design.
The straw includes a square hollow end at the top but does not function as a straw.
The fast-food chain announced the promotion on social media with a hilarious video of people reacting to it.
"While we can't change the iconic hollow spoon (a key piece of the mixing process), we can help ease the sting of your facepalm upon figuring out how to use it," McDonald's said in a statement.
To claim your free McFlurry, you'll scan the offer code in their app and then pick it up at a participating location.