You'll need more greens per cooked serving than you might think: For example, a medium-size head of escarole (about 4 to 5 cups raw) will reduce to 3/4 cup once it is blanched, squeezed dry, and chopped.
Cook greens in an enameled or stainless steel pot so their acidity doesn't react with the metal.
Refrigerate and keep greens unwashed until just before cooking; if they're stored even slightly damp, they rot quickly.
To wash, fill a sink with lukewarm -- not cold -- water. (Soil washes off more easily with lukewarm water.) Dunk the leaves into the water until all the grit is removed, or rinse under a gentle stream of water that won't bruise the tender leaves. Layer in paper towels in a salad spinner.
Remove the stems from older Swiss chard, spinach, kale, or beet greens: Fold over each leaf lengthwise with the underside facing you. Grasp the leaf with one hand and pull off the stem with the other hand.
Greens retain considerable water when they're blanched. Let them cool, and then gently squeeze out as much water as you can with your hands.
