Select a small saucepan in which the chestnuts may lay in more or less one layer. Add the butter, cilantro, and broth to cover by ½ inch. Bring to a simmer, partially cover, and simmer softly for about 20 minutes, or until the nuts are tender-firm and still holding their shape. Avoid boiling or the nuts will disintegrate. When done, some pieces will be intact while others will have broken apart. Set aside to cool. Use in your stuffing or serve as a side dish.