Kale:
How to Store: Keep kale unwashed (moisture speeds decay) in a plastic bag in the coldest section of the refrigerator, which is usually in the back.
Shelf Life: Because kale contains a lot of water, it doesn’t last long once it has been bought. Use it within 1 to 3 days of purchase for the tastiest results. Kale that has been sitting around can develop a strong bitter flavor.
Best Uses: Kale has a slight cabbage-y taste but none of the bitterness of some other greens, like broccoli rabe. Remove the leaves from the tough center stalk before sautéing or adding them to salads. Try adding 2 cups chopped leaves to a pot of soup. Simmer until tender, about 4 minutes. Kale is also a good substitute for spinach.
Try this delicious sounding recipe for kale and olive oil mashed potatoes! http://www.101cookbooks.com/archives/001566.html