Is it possible to make salty avocado Ice Cream without a machine?
On the question of dry ice, yes...it makes excellent ice cream using a kitchen aid and the beater in the standard bowl.  It is best if you pulverize the dry ice in a blender first.  You will want to avoid using too much (your base will become carbonated, but you can allow it to off-gas). Add a little at a time until the appropriate texture is achieved. Make sure it is not possible for someone to eat a chunk of dry ice!