1Heat oven to 425°F. In large roasting pan, toss cauliflower and broccoli with oil, salt and pepper. Roast uncovered 25 minutes, stirring occasionally, until vegetables are browned and tender.
2Meanwhile, in 1-quart saucepan, melt butter over medium-low heat. Stir in flour. Cook and stir until mixture is smooth and bubbly. Gradually add milk, stirring constantly until mixture boils and thickens. Stir in cheese until melted.
3Spoon roasted vegetables into serving dishes. Pour cheese sauce over vegetables; sprinkle with pine nuts.