Our dim sum gets to you frozen, because that's the best way to do it for a whole load of reasons.
It reduces food waste, preserves the taste and structure of the food and it allows our Hungry Dumplings to stock up and ensure they have a dim sum feast in the freezer for when the next pandemic strikes and we're all queuing up for toilet roll again. 
As such we wrap your dim sum boxes in the great natural insulator, wool, an eco friendly way to maintain the temperature of things.
Also wrapped up in this wooly jumper for dumplings is some dry ice, the coldest thing known to man (right?). This is commonly used in food transportation and although it will mostly have evaporated by the time it gets to you, you still need to be careful when taking out your dim sum box. Use gloves or a tea towel just in case - if you touch dry ice it'll hurt.