Preheat oven to 350 degrees F. Bring a large pot of lightly salted water to a boil. Add the cauliflower pieces to the boiling water; as soon as the water returns to a boil, set a timer for 2 minutes. Pour into a colander and let the cauliflower drain.

Place the cauliflower in a wide shallow casserole dish and season with salt and pepper. Pour the tomato sauce over it, sprinkle the cheese evenly over the top and then dot with the butter.

Cover with foil and bake for 20 minutes. Remove the foil and continue baking for another 5-7 minutes or until the cheese is bubbly and golden brown. 138 calories/serving; GL=2, Glycals=3