Cut broccoli into spears with 1/2-inch-wide stalks. In 2-quart round microwavable dish, place broccoli and water. Cover with plastic wrap, folding back one edge 1/4 inch to vent steam. Microwave on High 6 to 8 minutes or until hot and crisp-tender; drain.
In 2-quart saucepan, heat remaining ingredients over medium heat 6 to 8 minutes, stirring frequently, until cheese is melted and mixture is smooth. Pour over broccoli.