1 large bunch Rainbow chard
2-3 tablespoons olive oil
1 small white or yellow onion, small dice
3 medium garlic cloves, finely chopped
Freshly ground black pepper
2 (15-ounce) cans cannellini beans, drained and rinsed
¾ cups low-sodium vegetable or chicken broth
2 teaspoons kosher salt, plus more as needed
¼ cup fresh Italian parsley leaves, coarsely chopped
2 teaspoons white wine or red wine vinegar