Preheat an electric griddle to 350 degrees . In a mixing bowl whisk together milk, pumpkin puree, eggs, brown sugar, vanilla, cinnamon, nutmeg and ginger until well combined. Pour into a shallow dish. Butter griddle and dip bread into egg mixture , then rotate and coat opposite side. Transfer to griddle and cook until golden brown on bottom, then lift, butter griddle once more and flip french toast to opposite side and cook until golden brown. Serve warm with butter and maple syrup.