Resetting Favorite Channels on U-Verse

menu -> options -> channel -> edit/add favorites -> choose list -> uncheck all

Then you have to go back and start all over recreating your favorites.  Not sure what the point would be since you now have to go back through them all to recreate the list.  All the years I've had uverse there has never been a need to recreate the list except when getting a replacement receiver.

If this is an additional favorites list you could rename/delete list and recreate that list.