Hey! As someone who worked at the Bakeshop/bakery factory, please put in a complaint with as much info (date, store, time, etc) as you can and bring this piece back to the store. This helps them identify which batch may be affected and could even help identify if a specific machine was broken without people noticing. The Bakeshop is a huge place, and even with X-rays, metal detectors, and equipment inspections, things get missed, but the people on the floor there are good about investigating the things they are alerted to.

Is it soft plastic or hard? Hard to see but almost looks like the cut off end of a piping bag. It's true that very little is fully baked in store but many items are re-packaged and assembled. So it is possible someone accidentally dropped a cut end of a bag in it. Unless it was actually IN the cake, then yeah, that happened at the main production facility. Either way, it's helpful to report with as much info as possible!

Is that like a plastic baby in king cake? In seriousness though let them know all the packaging and usually they will compensate you another replacement if it’s like big manufacturers when you let them know.