1. Rinse ‘Em
No matter where you got your greens—farmers’ market, farm stand, CSA—it’s important to rinse them clean of any dirt or (eek!) bugs that may be clinging on the leaves. Use cold water so they don’t wilt, and be sure to rinse them thoroughly. You can give them a rough chop if you’d like at this point, which will make them easier to work with later on.
2. Blanch ‘Em
Bring a large pot of water to a boil—no need to salt it as you would for pasta, or for actual cooking. You’re just taking the raw edge off. Once the water’s boiling, add the clean greens and use tongs or a spoon to submerge them completely underwater. The water temperature will drop, so be sure to keep it at a boil by covering the pot or turning up the heat. Let the greens swim around in the boiling water for about 30 seconds.
3. Shock ‘Em
Using tongs or a wire spider strainer, transfer the greens to a large bowl or pot of ice water. This should be cold, cold, cold—plain tap water won’t do. The near-freezing water will stop the greens from overcooking, and help them retain their vibrant green color. Let them swim around in the cold water, adding more ice as necessary, for two to three minutes.
4. Squeeze ‘Em
Drain the water and ice, and gather the greens in your hands. Squeeze out as much water as possible—really put some muscle into it. Excess water will freeze, coating the greens with ice crystals that will degrade the flavor and texture as they sit in the fridge. It will take a few rounds of squeezing, so consider it your arm workout for the day.
5. Pack ‘Em Tightly
Once the greens are pliable but dry, pack them very tightly into baseball-sized spheres, as if you were packing wet snow into a snowball. They’ll stick together thanks to the dampness, but try not to manhandle them too much.
6. Freeze ‘Em
Space the balls of kale, chard, etc., out evenly on a sheet pan, maintaining their shape but not allowing them to touch. Cover the pan tightly with a sheet of plastic wrap; this will keep them from collecting ice crystals. Place it in the freezer for one to two hours, until the greens have frozen partially. Doing this rather than dumping them all in a bag will ensure that they stay separate and don’t form into one big lump. This is helpful when you remove them from the freezer at a later date; you can just take out as many or as few as you need.
7. Package ‘Em
Once the greens have frozen partially, transfer them to heavy plastic bag; remove as much air as possible when you seal it. Store in the freezer, and remove the balls as needed. The balls are perfectly sized, so you never have to thaw an entire package (and waste half of it) again.