Preheat oven to 425 degrees.
In a medium microwave-safe bowl, melt the butter. Add the brown sugar to the hot butter and whisk until smooth, about a minute.
Pour the brown sugar mixture into the bottom of a greased 9X13 pan.
If using chopped pecans, sprinkle evenly over the brown sugar mixture.
Cut the bread into 1-inch cubes and spread into the pan over the brown sugar mixture. Do not stir.
In a medium bowl, whisk together the eggs, milk, vanilla, salt, and cinnamon.
Pour the egg mixture over the bread and gently pat down the bread to make sure all the pieces are saturated.
Bake for 30-35 minutes or until the top is golden brown.
Serve with maple syrup and more chopped pecans, if desired.