Put
the leftovers in a container (from the lasagna* I love) in a bowl of
cold water t cool it down quickly. Since the container store heavily
stained tomato sauce, I assume it is stainproof. But you can't really
tell since it's black. Also, it is microwavable; hence, will be easy to
use microwave to defrost. Cover with a little piece of aluminum foil.
Write down the type of food on a little piece of paper and store
together in a ziplock bag. The bag can then be reused without cleaning.
Store in freezer.
*Keep
the paper package like this lasagna. Can be reused for cutting
vegetables over a chopping board to prevent cutting the board.