Making frozen kale or spinach cubes is an easy, cost effective way to always have greens on hand for smoothies.
Lightly steam kale & spinach (1-2 minutes). Let cool.
Once cooled, stuff into ice cube trays.
Add filtered water to the trays (this helps the cubes stay together).
Freeze until solid (4-6 hours). Pop out of ice cube trays & store in gallon sized plastic bag for up to three months.