"Why stir polenta forever when this delicious recipe works beautifully? I like to roast veggies (eggplant, zucchini, onion) while the polenta bakes, then when the polenta is done, top with roasted veggies and some chopped tomatoes, some spices, and bake another 20 minutes. It's dinner."
Preheat oven to 350 degrees F (175 degrees C). Grease a 2-quart casserole dish with cooking spray.
Pour water into the prepared dish; stir in polenta and salt.
Bake in the preheated oven until polenta is thickened, about 40 minutes. Stir in squash, sour cream, and Cheddar cheese. Continue baking until cheese is melted, about 10 minutes more. Let stand for 10 minutes before serving.