Pick your own fresh greens, this is kale, or pick up some at a local farmer's market. Wash greens thoroughly because most are grown in sandy soil which clings to leaves.
Cook on medium heat with just the water left on the greens from washing. Don't add any extra water, there will be plenty on the leaves themselves.
Greens will cook down to 1/2 - 1/4 the original amount in the pot.
Divide cooked greens into rigid freezer containers, not baggies.
Now, here's the secret to fresh-tasting frozen greens - fill the containers to 1/2 inch from the top with water. That's right! Greens will freeze into solid cubes and thaw nicely when you pop them out to cook one day next winter. Air space in freezer containers is what causes frozen food to deteriorate, to get frosty and taste old. Freezing in water solves that problem, but be sure you leave enough space at the top because water expands when it freezes.
Here are your greens, ready to fill your freezer and then your Crock-Pot or cassarole as part of your favorite recipes. This freeze-it-in-water method works with fresh herbs, too. Use ice cube trays to make little fresh herb cubes for future use.