At this point, the mixture is thick enough to add chocolate chips, crushed cookies, chopped nut, pureed fruit, or other flavor additions without them simply sinking to the bottom of the mixture again and again. Stir in any additions you want (puréed blueberries are added here to make Blueberry Ice Cream.
Note: Adding something at this point will un-freeze the mixture slightly. This is to be expected, so don't worry about it.