This is actually a Rick Bayless recipe from his cookbook Mexican Everyday, but we've used it a fair amount on those days we feel like not eating meat but still want to have tacos.
Ingredients
Slice up the chard into small slices. In a large skillet, heat the oil on medium-high. Cook the onions until soft, plus some garlic and red pepper flakes if you want. Put the chard in the skillet, add the broth. Cover the pan and reduce the heat to medium-low and cook until the greens are wilted and almost tender (about 5 minutes). Uncover, bring heat back to medium high and cook until almost dry. Salt as necessary. Enjoy.