Trim and wash cauliflower.
Cook, uncovered, in 1 inch boiling water, 20 minutes, or until just tender.
Drain; place in shallow baking dish; keep hot.
Combine salad dressing, cheese, parsley, lemon juice, and salt.
Fold in beaten egg whites.
Spread sauce over cauliflower.
Broil with top of cauliflower 6 inches from unit or tip of flame, 5 to 8 minutes, or until cheese sauce is puffed and golden brown.
If desired, sprinkle with additional cheese.