Portion our your baked good. And, make sure it is completely cooled before moving to the next step.
Place your portions on a cookie sheet in a single layer and pop into the freezer to flash freeze. Depending on how thick the frosting is, times may vary, but usually an hour or two will do it so the frosting is stiff enough to not get smushed and stick.
Remove from the freezer, and if desired, wrap each portion in plastic wrap or aluminum foil for extra protection.
Pop them into a freezer bag or airtight container.
Seal them up by placing the lid on the container or pressing all air from the bag and zipping it shut.
Write the date on the bag or container and then place it into the freezer.