Rinse kale well in large bowl of cold water. Place in colander; drain.
Discard any discolored leaves. To trim away tough stems, make "V-shaped" cut at stem end; discard tough stems. Stack leaves and cut into 3- to 4-inch pieces.
Melt 1 tablespoon butter with 2 tablespoons water in Dutch oven over medium-high heat. Add about 1/3 of kale; cook and stir 1 minute. Cover Dutch oven and steam kale 3 to 5 minutes or until kale is wilted and tender but not soft, stirring occasionally.
Transfer to a large bowl; cover to keep warm. Steam remaining kale in two batches using 1 tablespoon butter and 2 tablespoons water for each batch.