Beetroot, witlof, labne and orange salad

Name: Beetroot, witlof, labne and orange salad
Prep time: 30 min
Cook time: 1 h 15 min
Total time: 1 h 45 min
Cuisine: European
Ingredients: 250 gm thick Greek-style yoghurt; 750 gm rock salt; 2 bunches beetroot (about 8), trimmed; 2 witlof, leaves separated; 2 oranges, segmented; ½ onion, thinly sliced into rings; 1½ cups (firmly packed) flat-leaf parsley leaves (about ½ bunch); 1 cup dill sprigs (about ½ bunch) (firmly packed); 100 ml extra-virgin olive oil; 50 ml sherry vinegar