Although the vibrant pink color of this Middle Eastern dip is startling, the flavor is superb. There are many versions. Sometimes the beets are puréed and blended into the yogurt; other times, they are simply sliced or cubed; still other times, a little tahini is blended in for a deeper, richer flavor. In this recipe, the beets are simply grated with the shredding disk of a food processor, then folded into thick, creamy yogurt. Serve as a dip or an accompaniment to fish. Cook time includes chilling time.