Preheat oven to 350°F.
Slice the loaf of bread into 1-inch cubes, cutting off the crust. It will make about 10-11 cups of bread.
16 ounces Hawaiian sweet bread
Place the bread cubes on a baking sheet and bake for about 30 minutes, turning twice. (you can skip this step if you're tight on time, but the toasted bread makes this extra tasty!)
In a large bowl, whisk together the hot chocolate, eggs, vanilla, and salt. Set aside.
3½ cups prepared hot chocolate, 1 teaspoon pure vanilla extract, 5 large eggs, ⅛ teaspoon kosher salt
Place one layer of bread cubes into a 9x9-inch baking dish. Scatter ¼ cup chocolate chips and ¼ cup mini marshmallows over the bread.
½ cup milk chocolate chips, 2 cups mini marshmallows
Top with the rest of the bread and pack tightly. Sprinkle with the remaining ¼ chocolate chips and ¼ cup of the marshmallows.
Pour hot chocolate mixture into the baking dish. The liquid should come to almost to the top of the dish with a bit of the bread still exposed. Cover with foil.
Refrigerate overnight or for at least 2 hours.
When ready to prepare, preheat oven to 325°F. Allow the bread pudding to rest on the counter while the oven heats.
Bake, uncovered, for 45-50 minutes or until the bread cubes are crisp and browned and a toothpick inserted into the middle is firm.
Remove the dish from the oven and top with the remaining 1½ cups mini marshmallows.
Switch your oven settings to broil and broil for approximately 3-4 minutes, or until the marshmallows are toasted to your liking. Watch it closely, the broiler can burn the marshmallows easily.
Let sit for about 20 minutes before serving, it will be very hot. Slice and serve.