Scrub the beets well and trim off any roots. Place them in a large pan, and cover with plenty of cold water.
Bring the beets to a boil, and cook at a medium temperature, covered, for 45 minutes or until a knife slide easily into the flesh of the largest beet.
Drain the beets. Peel them as soon as they’re cool enough to handle—the peel will slide off between your fingers. Chop the beets into coarse dice. Place in a medium-sized bowl.
In a separate small bowl, blend the vinegar, olive oil, salt and pepper, sugar, and cumin. Pour over the beets, preferably while they’re still warm. Stir the onions into the salad.
Taste to adjust seasonings if desired. Cover the bowl and refrigerate the salad for at least an hour. When ready to serve, spoon the salad out onto a dish and spoon tahini over it. Garnish with parsley and enjoy.
