Make-Ahead Breakfast Casserole

Preheat oven to 400 °. Arrange bread cubes in a single layer on a baking sheet. Bake at 400 ° for 8 minutes or until toasted. Heat a medium skillet over medium-high heat. Coat pan with cooking spray. Add sausage to pan; cook 6 minutes or until browned, stirring to crumble. Combine sausage, bread, and onions in a large bowl. Combine milk, cheese, eggs, and egg substitute in a medium bowl, stirring with a whisk. Add milk mixture to bread mixture, tossing to coat bread. Spoon mixture into a 2-quart baking dish coated with cooking spray. Cover and refrigerate 8 hours or overnight. Preheat oven to 350 °. Uncover casserole. Bake at 350 ° for 50 minutes or until set and lightly browned. Sprinkle with parsley; serve immediately.