Recipes Ingredients Vegetables Spinach Recipes Blanched Greens 4.0 (1) Close Credit: Bryan Gardner This technique can be used for leafy greens such as collards, kale, Swiss chard, and spinach. Blanched greens can be stored in an airtight container in the refrigerator for up to 4 days. See how to use blanched greens. Directions Remove leaves from stems. (Swiss chard stems are edible, so save and cook them) Blanch greens in a large pot of boiling salted water, 15 seconds (spinach and chard) to 2 minutes (kale and collards); drain. When cool enough to handle, squeeze out excess liquid; let cool completely in a single layer on a rimmed baking sheet. Greens can be stored in an airtight container in refrigerator up to 4 days. Cook's Notes Cooked-Greens YieldsThat bundle of fresh greens may look enormous—until it cooks down. If you need a particular amount, weigh it in the store, or play it safe and buy two bunches.1 lb. collards = 2 cups1 lb. kale = 2 cups1 1/2 lb. spinach = 1 1/2 cups1 lb. Swiss chard = 2 cups