Whisk together juices, vinegar, and oil in a large bowl.
Toss mushrooms with vinaigrette and marinate 15 minutes.
Transfer mushrooms to another bowl reserving vinaigrette.
Place mushrooms on braai griddle and turn frequently until golden brown. (Mushrooms cooked over a grill will cook very fast and become dried out, so move them around the fire for better heat control - don't let them burn!)
Transfer mushrooms back to vinaigrette when grilled, then toss with sea salt and serve. Chef's Tip:
If your sea salt is very granular and pebble like, crush it using the flat side of a large heavy knife or the bottom of a heavy skillet.
Reprinted with the permission of Lynn Woodward of the South African
Mushroom Farmers’ Association