Snap the beans into 1-inch pieces. To chop the chard, first cut off the thickest parts of the stems. Chop them into ½ inch pieces and set aside. Pile the leaves on top of each other, run your knife lengthwise once or twice down the leaves, then crosswise into about 1-inch pieces. Set aside separately from the stem pieces.

Heat a skillet on medium-high, add oil. Once oil has heated through, add the chard stem pieces. Sauteé a minute or two, just until the pieces barely soften. Add the leaves, beans, and balsamic. Cover the pan and turn heat to low. Cook another minute or two, until beans have just started to soften but still have a little crunch. Serve hot