Preheat oven to 350 degrees F. Add bread cubes to a large baking sheet in a single layer. Bake for 15 minutes, stirring halfway through, or until toasted; set aside.: You will notice a warm, toasty smell once the oven reaches temperature, which primes the pan for evenly drying the brioche . Toasting the bread first helps it form a slight crust and prevents sogginess, giving textural contrast. A common mistake is skipping the toasting, which can leave the interior overly wet and the top under textured; toast in a single layer so the cubes cook evenly.
Meanwhile, chop 12 ounces of chocolate. Add 8 ounces chopped chocolate to a medium mixing bowl, set remaining 4 ounces chocolate aside.: The visual cue you want is evenly spaced cubes so hot air can circulate and dehydrate each cube uniformly. As they toast, you will hear faint sizzling and smell a nutty, warm aroma that signals the Maillard reaction is starting. Avoid overcrowding, which traps steam and prevents crisping.
Microwave the heavy cream and milk (preferably in a glass liquid measuring cup) until simmering, but not boiling, about 2 minutes. Pour over 8 ounces chopped chocolate in the bowl and let stand for 3 minutes, then vigorously whisk until chocolate is completely smooth; set aside.: Expect the cubes to take on a light golden hue and a firm, dry texture when done, which tells you they will absorb custard without disintegrating. Stirring midway ensures even color. A mistake is leaving them too long until deeply brown, which can make the pudding dry in places.
In a large mixing bowl, whisk together the eggs, egg yolks, sugar, cocoa powder, vanilla extract, cinnamon, salt and nutmeg. Slowly whisk in the chocolate mixture until smooth (this is now the chocolate custard).: When you chop chocolate, the pieces melt more predictably and give you pockets of melted chocolate within the pudding. The sound is silent but the benefit is visual, a mix of smooth custard and glossy melted streaks. Do not use uneven giant chunks that will not melt through the custard.
Add half of the bread cubes, half of the remaining chopped chocolate (2 ounces), and half of the chocolate custard to a lightly greased 9×13 casserole dish. Stir until evenly coated. Add the remaining bread cubes and chopped chocolate (2 ounces) to the chocolate custard in the bowl. Stir until evenly combined then pour into the pan and spread into an even layer.: Having the reserved chopped chocolate allows you to fold in bits that soften but do not fully disappear, creating texture contrast. The bowl should be dry and warm from your hands to prevent seizing. If the chocolate gets warm from your hands, it melts too quickly and can become clumpy.
Cover the pan with foil and allow to sit at room temperature for 45-60 minutes, until the bread soaks up most of the custard.: You want small bubbles around the edges but no rolling boil, which keeps the dairy from scalding and producing off flavors. A sweet, milky steam will rise and the mixture will wobble slightly when moved. Overheating can cause a film or tiny curdling, so watch closely.
Bake the covered bread pudding for 45-50 minutes, until the edges appear set and a toothpick inserted in the center comes out with few moist crumbs, but no raw/wet custard. The last 5 minutes of cooking, make the ganache.: After resting, the chocolate will soften and the aroma deepens into rich cocoa. Vigorously whisking creates a glossy emulsion, smoothing fat and liquid together. If bits remain, letting it sit another minute then whisking will rescue it; don’t over whisk into aeration which can make the ganache less silky.
Add heavy cream and corn syrup (if using) to a microwave safe bowl and microwave for 2 minutes or just until simmering. Add chocolate and give it a swirl so the chocolate is covered. Let stand for 3 minutes. After 3 minutes, vigorously whisk in circular motions until chocolate is melted and completely smooth.: The mixture should become pale and slightly thickened, releasing fragrant spices that lift the chocolate . This step builds the backbone for the custard, and whisking evenly prevents pockets of dry cocoa. A common error is under whisking, leaving streaks of cocoa powder that will clump in the custard.
Drizzle desired amount of ganache over entire bread pudding or on individual servings. Serve with other desired toppings such as whipped cream, ice cream and/or berries.: As you combine them, you will sense the temperature evening out and the custard gaining viscosity, becoming glossy and pourable. The smell moves from eggy to fully chocolate. Adding too fast risks cooking the eggs, so slow incorporation protects the custard texture.
Add half of the bread cubes, half of the remaining chopped chocolate (2 ounces), and half of the chocolate custard to a lightly greased 9×13 casserole dish: The first layer soaks and settles, absorbing flavors; the visual will show bread turning darker as custard penetrates. Distributing chocolate pieces creates pockets of molten joy. Avoid pressing down hard, which can compress the bread and result in uneven soak.
Stir until evenly coated: You will notice the bread darken and glisten, and small ribbons of chocolate will be visible. This tactile motion ensures every cube is saturated. Commonly people skimp on stirring then find dry pockets after baking, so be thorough but gentle.
Add the remaining bread cubes and chopped chocolate (2 ounces) to the chocolate custard in the bowl: The second layer finishes distributing custard and chocolate so flavor is consistent from top to bottom, and you can see the mixture becoming cohesive. If some cubes are especially dry, press them lightly to help absorption.
Stir until evenly combined then pour into the pan and spread into an even layer: Look for an even surface and consistent color, a sign the custard is uniformly distributed. A level layer bakes more predictably. Uneven distribution leads to some areas that set while others remain soupy.
Cover the pan with foil and allow to sit at room temperature for 45 to 60 minutes, until the bread soaks up most of the custard: This resting time is crucial; the texture evolves from separate elements to one cohesive pudding. You will see the bread swell slightly and become saturated; the aroma will mellow and deepen. Skipping this means a less integrated texture and pockets of dry bread.
Bake the covered bread pudding for 45 to 50 minutes, until the edges appear set and a toothpick inserted in the center comes out with few moist crumbs, but no raw or wet custard: As it bakes the top will slightly puff and the edges will firm, giving audible gentle crackles as moisture escapes. The interior should be custardy not runny. A common mistake is pulling it out too early, leaving a raw center; rely on the toothpick test rather than time alone.
The last 5 minutes of cooking, make the ganache: Prepare the ganache while the pudding finishes so it is warm and pourable when the dessert comes out, creating a glossy finish that melds with the hot surface. If you wait too long and the ganache cools, it will thicken and lose shine, so time it with the oven.
Add heavy cream and corn syrup if using to a microwave safe bowl and microwave for 2 minutes or just until simmering: You will see small bubbles form around the edges signaling readiness. Warm cream extracts and softens chocolate flavors without scorching. Boiling will break the emulsion, so stop at simmer.
Add chocolate and give it a swirl so the chocolate is covered: This action ensures even melting and prevents dry pockets. After a short rest the chocolate will bloom into the cream, releasing a rich scent. If chocolate looks grainy, allow a little extra rest before whisking.
Let stand for 3 minutes then vigorously whisk in circular motions until chocolate is melted and completely smooth: The whisking action creates a silky, shiny ganache and you will notice its glossy surface and fluid ribbon when lifted. Overcooling can thicken it; if that happens, brief gentle warming restores gloss.
Drizzle desired amount of ganache over entire bread pudding or on individual servings: The warm ganache will settle into crevices and add a decadent sheen, enhancing both look and mouthfeel. Drizzling while warm creates a beautiful glossy finish. If you over pour, the pudding can become overly sweet and soggy, so apply with restraint.
Serve with other desired toppings such as whipped cream, ice cream and or berries: Serving warm contrasts textures and temperatures, the chilled whipped cream or ice cream melting into the warm pudding for a perfect bite. Choose one accent to keep the balance. Serving straight from the fridge removes the pleasure of warm custard, so reheat slightly if needed.