How to bring frozen top tier of cake home on the plane

I am assuming you will be bringing it home to eat on your year anniversary? I did that for my first marriage and I can almost guarantee you that you will not want to eat your cake after it has been frozen for a year. It was crusty and tasted like cardboard! I would suggest getting some really good pictures of the top layer and having it recreated for your one year anniversary. If you do insist on keeping it, I would see if a local Las Vegas bakery can hold it until you are home and then overnight it to you. They will know how to package it, keep it cold, ship it etc. I wouldn't try to fly with it. Good luck!!

We’re traveling on a plane - 5 hours from UT to PA. We’re boxing the cake and taking as carry on to eat at home after the wedding. It’s allowed.

I brought cake in a Tupperware on the plane for our honeymoon. I just carried it on, it was a bigger Tupperware, and put it under the seat in front of me. It got a little smooshed.
I don’t think freezing it before hand would be best, it would probably defrostbeforw you got home.

Buy a fresh cake on your one year and enjoy your cake in Vegas while it tastes good. Our baker includes a free anniversary cake made fresh on our one year anniversary which is awesome because I know how gross cake tastes in the freezer after just a few months.

Also if you freeze your cake before getting on the plane it’ll completely defrost on the trip back no matter what so you’re freezing twice, it’s going to taste pretty bad in a year.

We fly with frozen meat often, but more on 2 hour flights than anything. It also depends on the airline, we always fly southwest. If you can, I'd put it in a deep freeze to really FREEZE it. If you can't, in a freezer overnight at least. I'd wrap the cake in plastic wrap several times, then foil, then probably a bag to protect from water. I'd get a good small cooler (even a small Yeti if you can afford one or have one) and pack it with those frozen reusable packs or ice in bags. The only thing is airlines will make you take out ice if it's liquified at all so I'm not sure how the layover and second flight would work since it would obviously melt. I assume in the airport you could find ice at a vending machine so maybe just bring extra ziploc bags to fill it at the airport? If you use dry ice, they will make you leave the lid cracked so the pressure doesn't get too high. Dry ice is a pain in my opinion so we avoid it. You can also pack the cooler on the inside with styrofoam on each wall to help with insulation.

We are just having our bakery remake our cake on our 1 year but that may not be an option from NV to Hawaii.

Could you ship it home express instead? I think you might have a bit more flexibly there, too. I mean, if you can get a Chicago-style pizza shipped on ice anywhere in the US, and meal delivery companies like Blue Apron can manage, I have to think shipping would be a viable route.