Collard greens are considered a traditional side dish in the southern parts of the United States, and are even included as part of a New Years celebration meal because their leaves resemble folded money. Braised with ham hocks, collards become tender and velvety, taking on the flavor of the smoky broth. Wrap unwashed greens in a damp paper towel and store in an airtight plastic bag. Place the bag in the refrigerator for up to five days.