Cut one pound of cinnamon raisin nut bread into cubes that are roughly ¾” in size.
If the bread cubes are not dried out and are still fresh, toast them on a sheet tray in the oven at 300F for about ten minutes.
Set the dried-out cubes of bread aside for later.
Combine the 2 cups of whole milk and the 2 cups of heavy cream in a sauce pot on the stove.
Add the white and brown sugar.
Turn the heat to medium, and stir until the sugar is dissolved.
Continue to heat the liquid until it reaches roughly 165F, but before it is simmering.
Whisk the whole egg together with the 8 egg yolks in a small bowl.
Slowly add the whisked eggs to the hot milk and cream mixture, whisking while you add the eggs very slowly.
Turn the heat off the stove, and add the 8 Tbsp of butter.
Stir until the butter has melted.
Add the ground cinnamon, ground ginger, corn starch, Kosher salt, and vanilla extract, and whisk to combine.
Pour the liquid mixture into a large bowl, and add the bread cubes from earlier.
Add the pecans and walnuts, and mix until the bread is covered in the bread pudding liquid.
Cover the mixture with plastic wrap, and store in the fridge for 8-12 hours.
When the bread has fully soaked in the liquid and is ready to be baked, prepare your baking dish by coating the insides of the dish liberally with softened butter.
Preheat your oven to 350F.
Pour the soaked bread cubes and bread pudding liquid and nuts into the buttered baking dish.
Cover the dish lightly with aluminum foil.
Bake at 350F covered with aluminum foil for roughly 25 minutes.
Remove the aluminum foil, and bake for an additional 20-25 minutes.
Remove the bread pudding mixture from the oven, and allow to cool slightly before serving.