zip-top and/or freezer bags
ice water and hot water
To avoid excess moisture, wrap the whole bunch of kale in a layer of paper towels, and store in a supermarket plastic bag or a zip-top plastic bag in the refrigerator crisper drawer. The kale should keep for 1 week.
Because kale leaves are so hardy it is one of the only greens that you can wash and prep days in advance. Stem, slice or tear the leaves, rinse, then dry well in a salad spinner or with kitchen towels. Store the prepared leaves, wrapped in a paper towel in a zip-top plastic bag, for up to 3 days.
If you aren’t going to get to the kale within a week, you can freeze kale leaves to use in soups or green smoothies later on. All it takes is a quick blanch and a couple ofsteps in the freezer.