Preheat oven to 350 degrees. Cook vegetables until crisp-tender. Arrange vegetables in greased 2-quart casserole.
To make the sauce, melt margarine in medium saucepan over medium heat. Stir in flour until smooth; cook 2 Minutes. Gradually stir in milk. Cook until thickened, stirring constantly. Season to taste with salt and pepper. Add cheese, stirring constantly until cheese is melted.
Pour sauce over vegetables and sprinkle with cilantro. Bake 15 Minutes or until heated through.