Nearly all swirls and mix-ins are added after the ice cream has been churned. Otherwise, swirls would simply blend into the ice cream as it churns, and mix-ins would sink to the bottom. When the ice cream has finished churning, get a freezer-proof plastic storage container. This is the time to add swirls and mix-ins. For swirls, transfer two scoops of ice cream to the storage container, then drizzle (or spoon) the chocolate (or jam or peanut butter) over the ice cream. Be careful not to overmix it into the ice cream. Repeat with two more scoops of ice cream, more drizzle, and so on, until all of the ice cream has been added to the storage container and mixed with the swirl. Move quickly or the ice cream will melt. Mix-ins are easier. Just stir them in as you transfer the ice cream to the storage container. Use as little or as much as you’d like. Our goal in the shop is to go overboard with mix-ins, but perhaps you prefer a lighter hand. It’s up to you. All the recipes for mix-ins make approximately one tray, but that it is more than necessary for the recipe of ice cream. Enjoy the leftovers!