Remove the prime rib steak from the fridge an hour in advance to allow it to settle to room temperature.
Bring a large pot of water to the boil and cook the potatoes until tender.
Cut the broccoli into small pieces and cook them in a pan with boiling water for a couple of minutes making sure the heads stay slightly crunchy. Drain.
Thread the mushrooms and broccoli onto a skewer and grill them for a few minutes on each side with the sliced aubergines and potatoes.
Grill the prime rib steak to your taste. Remove the meat and leave it to rest for 10 minutes (cover it during this time).
Prepare the blue cheese dressing by mixing the cheese, parsley and garlic together whilst adding olive oil until you get your preferred dressing consistency.
Slice the prime rib steak and serve it with the barbecued vegetables and the Saint Agur dressing.