Preheat the oven to 350 degrees Fahrenheit.
Generously butter a 9 x 13-inch baking dish.
Cut the pumpkin bread into 1/2- to 1-inch cubes.
Spread the bread cubes on a baking sheet.
Toast the bread cubes at 350 degrees Fahrenheit for 25 minutes.
Stir the bread cubes once during baking to ensure even toasting.
Toast for an additional 10 minutes until the bread is as dry as croutons.
Transfer the toasted bread cubes to the prepared baking dish.
In a large bowl, whisk together the whole eggs and egg yolks until well blended.
Add the half-and-half, heavy cream, granulated sugar, and vanilla extract to the egg mixture.
Mix until the sugar is fully dissolved and the mixture is smooth.
Pour the egg mixture evenly over the toasted bread cubes in the baking dish.
Gently press the bread cubes down so they absorb the egg mixture.
Let the mixture sit for about 10-15 minutes.
Drizzle the melted butter and melted chocolate (or hazelnut spread) over the top.
Cover the baking dish with aluminum foil.
Bake in the preheated oven for about 45-50 minutes.
Remove the aluminum foil for the last 10 minutes to brown the top slightly.
Serve warm.