1. Heat a large nonstick skillet over medium-high heat. Coat pan with cooking spray. Add sausage to pan; cook 5 minutes or until browned, stirring and breaking sausage to crumble. Remove from heat; cool.
2. Combine milk and next 6 ingredients (through eggs) in a large bowl, stirring with a whisk.
3. Trim crusts from bread. Cut bread into 1-inch cubes. Add bread cubes, sausage, and cheddar cheese to milk mixture, stirring to combine. Pour bread mixture into a 13 x 9–inch baking or 3-quart casserole dish coated with cooking spray, spreading egg mixture evenly in baking dish. Cover and refrigerate 8 hours or overnight.
4. Preheat oven to 350°.
5. Remove casserole from refrigerator; let stand 30 minutes. Sprinkle casserole evenly with paprika. Bake at 350° for 45 minutes or until set and lightly browned. Let stand 10 minutes.