Preheat oven to 350 degrees F. Coat a large skillet with cooking spray. Heat over medium heat. Cook onion and bell pepper in the hot skillet until tender. Cool slightly. Lightly coat a 2-quart rectangular baking dish with cooking spray; set aside.Advertisement
Meanwhile, combine corn kernels, cream-style corn, corn muffin mix, and egg substitute in a large bowl. Stir in the cooled vegetables. Transfer the mixture to the prepared baking dish.
Combine sour cream and Cheddar in a small bowl. Spoon in small mounds over the corn mixture. Bake in preheated oven for about 1 hour or until set. Let stand for 10 minutes before serving.