Trim the beets of their leaves and stems. Place each type of beet in a separate foil packet with 1 tbsp EVOO, 1 tsp sherry vinegar, and some salt. Place the three packets on a roasting pan and roast at 350 degrees for 45 minutes or until tender.
Remove beets from oven and allow to cool. Using a dish towel, rub the beets to remove the skin and discard the skin. (Please use a towel you don’t care about – the beet juice WILL stain it.) Cut the beets in halves and marinate in a quarter cup of EVOO and 2 tbsp sherry vinegar.
Cut the halloumi into cubes and fry in a pan with oil until golden. Mix the yogurt with the lemon juice, dried mint, salt, and a quarter cup of EVOO.
To dress, place the marinated beets in a bowl, and garnish with the yogurt dressing and fried halloumi.