Preheat your oven to 350 degrees
Cut the entire loaf into 1 inch cubes (removing most of the crust) and place them onto baking sheets
Toast the bread in a 350 degree oven for 10 minutes or until they feel very dry and the edges are just lightly golden
Transfer the toasted bread crumbs onto a heat proof surface and let them cool for a few minutes
Meanwhile, combine 1 3/4 cup of whole milk and 3/4 cup of heavy cream in a medium sauce pan and place over medium heat
Place 6 ounces of chopped semi-sweet chocolate into a large glass bowl and set aside
Combine 3 eggs, 1/3 cup of granulated sugar, 2 teaspoons of vanilla extract, 1 teaspoon of espresso powder and 1/4 teaspoon of salt in a small bowl and whisk until smooth and set aside
Once the milk and cream mixture is simmering, pour it over the chopped chocolate and let it sit for 5 minutes undisturbed
Whisk the cream and chocolate until all of the chocolate has melted
Slowly add the egg mixture into the chocolate cream and whisk to combine
Use 1 tablespoon of softened butter to grease a 2 quart baking dish
Transfer about 1/3 of the chocolate cream mixture into a separate bowl and set aside
Add the toasted bread cubes into the large bowl containing 2/3 of the chocolate cream mixture and toss until all of the cubes are coated
Transfer half of the chocolate coated bread cubes into the buttered baking dishÂ
Sprinkle 1/2 of the dark chocolate chunks over the chocolate coated bread cubes
Add the remaining chocolate coated bread cubes and top with the remaining dark chocolate chunks
Drizzle the remaining chocolate cream mixture over everything
Cover and let sit at room temperature for 30 minutes
Bake at 350 degrees for 40-50 minutes or until the chocolate cream appears to be set
Transfer the baking dish onto a heat proof surface and let it rest for 10 minutes before serving
Garnish with whipped cream or ice cream (optional)