Freezing cilantro is a great way to preserve the often abundant harvest one can get from this biennial herb. Its unique flavor survives some time in the cold quite nicely, even if its pretty leaves don't look their best when the herb is thawed out. Depending on how you want to use the cilantro in the end, there are two methods for freezing, both of which are quite easy.
But, no matter which method you choose, it is important to start with perfectly clean cilantro. Give it a swish in cool water to get rid of any dirt, grit, or dust clinging to its leaves. Then, because excess water will create damaging ice crystals, be sure to dry it thoroughly. One way to do this is to spin it in a salad spinner and then lay on layers of paper towel. Starting at one end of the towel, roll up, encasing the cilantro, to soak up any bits of excess moisture.
Method 1: Freeze Cilantro Leaves in a Bag
This method is the easier choice since you are simply placing the leaves in a bag and freezing. Once the cilantro is defrosted, the leaves won't look great, so with this method, it is best to use the herb as an ingredient stirred into recipes rather than as a garnish.
To freeze the cilantro in a bag, place one freezer bag into another to create a "double bag." Remove the leaves from the stems and add the cilantro leaves to the bag; push out as much air from the bags as possible and seal tightly. Stick the bag in the freezer and simply pop off the leaves as you want to use them.
Cilantro frozen this way works best in dishes where it is cooked, such as turkey tacos or potatoes in cilantro sauce, or in those recipes where the leaves are really mixed in, such as chile cilantro guacamole.
If you have a whole bunch of frozen stems left over when all the leaves have been plucked off, they're perfect for dunking into a pot of drunken black beans, where they'll bring all their great flavor to the dish.
Method 2: Freeze Cilantro In Cubes
This freezing method creates small cubes, ideal for popping into soups or stews to add a burst of cilantro's unique, fresh flavor (plus a nice hit of green). For this method, before the cilantro can be put into the ice cube tray, it needs to be pureed with a liquid. Simply whirl the cilantro in a blender or food processor with enough water or olive oil to make a thick puree. Pour into a clean ice cube tray or small covered containers and place in the freezer. Once frozen through, transfer the cilantro cubes to a resealable plastic bag for long-term storage—they will last in the freezer up to 6 months.