Preheat oven to 350 degrees F. Grease a 8x8-inch baking dish with nonstick cooking spray and set aside.
Combine the oats, brown sugar, cinnamon, salt, and baking powder in a large bowl. Combine the milk, applesauce, butter, egg, and vanilla in a medium bowl. Add the milk mixture to oat mixture; stir well. Stir in raisins or dried cranberries.
Pour oatmeal mixture into prepared pan and bake for 20-22 minutes or until oatmeal is set and golden brown.
Notes-This is an easy recipe to double, so if you are serving a crowd, double and bake in a 9x13 pan. If you want to add toppings you can add nuts, fruit, brown sugar, cinnamon, milk, etc. I always add a dash of cinnamon to my bowl!