Tangy Mustard Cauliflower
["1 medium head cauliflower or 10 oz. pkg. frozen", "1/2 c. salad dressing or mayonnaise", "1 Tbsp. chopped onion", "1 to 1 1/2 tsp. prepared dry mustard", "1/2 c. shredded American cheese or Cheddar"]
["Cook cauliflower in a small amount of water, loosely covered, 15 to 20 minutes (fresh whole), 8 to 12 minutes (fresh flowerets) or cook frozen as directed on package.", "Drain well.", "Remove cauliflower to heatproof dish.", "Combine salad dressing and onion and mustard.", "Spread on hot cauliflower; sprinkle with cheese. Bake at 350\u00b0 until cheese melts (or leave in saucepan, spreading with salad dressing mixture and sprinkle with cheese; cover and let stand until cheese melts, about 3 minutes).", "Serve immediately."]
["head cauliflower", "salad dressing", "onion", "mustard", "American cheese"]