Preheat oven to 350°F. Spray a 10-inch springform pan with cooking spray. Set aside.
In a large bowl, stir together eggnog, sugar, vanilla, cinnamon, nutmeg, egg and egg whites. Add in bread cubes. Stir to combine. Leave mixture sit for 10 minutes.
Pour mixture into springform pan. Bake 1 hour. Let stand 10 minutes and release the sides of the springform pan. Top with powdered sugar and raspberries, if desired.