Cut the bread into 1” cubes. Spread out on a baking pan. Bake in the oven at 200 degrees for an hour or until dried out.
Set the butter for the topping out to soften.
In a large bowl, whisk together the cream, milk, eggs, sugar, vanilla, cinnamon and nutmeg until fully combined.
Spray a 9” x 13” baking dish with cooking spray. Arrange the dried bread cubes in the dish. Pour the custard mixture evenly over the bread. Press the bread cubes down into the custard.
In a separate bowl, combine the butter, brown sugar, corn syrup and cinnamon with a electric mixer until fully combined. Add the chopped pecans and mix on low until combined. Crumble this mixture evenly over the top of the bread mixture. Cover and refrigerate overnight.
To bake, preheat the oven to 350 degrees. Put the oven rack in the lower half of the oven. Remove the casserole from the refrigerator 20 minutes prior to baking. Uncover the casserole and place into the oven. Bake for 55 minutes, check after 30 minutes and if the top is getting brown, cover it with foil. When the casserole has puffed up and the top is brown, remove from the oven. Check to make sure it is done in the middle. If the middle is still wet, put back into the oven for 5 minutes. After the casserole is done, let it sit for 5 minutes before serving.
Cut into squares and serve.