cooking.nytimes.com
Collard greens don’t have the cachet of popular greens like black kale and rainbow chard. This is probably because collards have a stronger flavor and tougher leaf than many other greens. They do stand up to longer cooking, but they don’t require it. In this stir-fry, they stood in for more traditional greens like Chinese broccoli or bok choy and cooked up crunchy. As a bonus, collards are a great source of calcium. According to the Harvard School of Public Health, a cup of cooked collard greens has more calcium than a glass of skim milk.