Preheat oven to 375°F. Spray the baking dish with nonstick cooking spray.
In a medium bowl, combine oats, baking powder, and salt.Add milk, egg, brown sugar, maple syrup, and vanilla. Mix well. Pour the mixture into the prepared baking dish.
Bake approximately 35 minutes or until golden and cooked through.Top with fruit and nuts if desired and a splash of milk.
Store leftovers in an airtight container for up to 4 days.