PLACE cauliflower and broccoli in 2-L microwaveable dish. Add water; cover. Microwave on HIGH 8 to 10 min. or until vegetables are tender; drain. Set aside.
MICROWAVE cream cheese spread and milk in 2-cup microwaveable measuring cup or medium bowl 1 min. or until cream cheese is melted and mixture is well blended when stirred. Add sour cream; mix well. Pour over vegetables; sprinkle with Cheddar cheese. Microwave 2 min. or until cheese is melted.
MIX cracker crumbs and Parmesan cheese. Sprinkle over vegetables.