It may be Monday, but it’s gunna be a good day! McDonald’s is giving away FREE Egg McMuffins to mark their 1st ever Egg McMuffin Day, USA Today reports. The classic breakfast sandwich debuted 50 years ago in 1971. To score free breakfast, download the McDonald’s mobile app and register an account. The promotion runs between 6 and 10:30 a.m. local time. No purchase is necessary at participating locations.