McDonald's Wiki
Custard Pie

The Holiday Pie was first introduced in 1999, during the holiday season in promotion for Toy Story 2. Not until 2012, it became a official item.

The pie is a flaky, crispy dough covered in thin white icing and tiny confetti sprinkles. The inside is filled with golden yellow custard, briefly visible through a few slits on the surface of the crust.

It is arguably one of the rarest McDonald's menu items to date and, unlike the regular apple pie, the Holiday Pie is usually, but not always, available during the holiday season, from November through December.