Make your smoothie kit. Combine the kiwi, kale, pineapple, and ginger in a small plastic bag. Freeze for at least 8 hours or up to several weeks.
When you're smoothie-ready, add half the kefir to the blender, then the smoothie kit. Pulse until as smooth as possible, scraping every so often. Add the rest of the liquid and blend until smooth, supplementing with more kefir if necessary.
Emma is a writer and recipe developer at Food52. Before this, she worked a lot of odd jobs, all at the same time. Think: stir-frying noodles "on the fly," baking dozens of pastries at 3 a.m., reviewing restaurants, and writing articles about everything from how to use leftover mashed potatoes to the history of pies in North Carolina. Now she lives in Maplewood, New Jersey with her husband and their cat, Butter. Stay tuned every Tuesday for Emma's cooking column, Big Little Recipes, all about big flavor and little ingredient lists. And see what she's up to on Instagram and Twitter at @emmalaperruque.