Leafy greens made easy. Dark leafy greens are an excellent source of folic acid, an important B vitamin. Wilting them makes for a simple side dish. Here's how: Rinse greens, such as spinach, chard, kale or beet greens, thoroughly in cool water. Transfer them to a large microwave-safe bowl. Cover with plastic wrap and punch several holes in the wrap. Microwave on High until wilted, 2 to 3 minutes. Squeeze out any excess moisture from the greens before serving.