In a small saucepan, melt the [butter] and [brown sugar] with the [corn syrup] over medium heat. Stir until smooth and bubbly. I always let Olivia hold the whisk for this part, she says it smells like “warm candy morning.”
Pour the caramel mixture into your 9×13 baking dish and spread it evenly. This will become the glossy, crackly topping once baked.
Lay the sliced [challah bread] over the caramel layer. Overlap slightly if needed, this creates a beautiful, rustic look. Olivia loves arranging the slices “like little blankets.”
In a large bowl, whisk together the [eggs], [whole milk], [heavy cream], [vanilla], [cinnamon], [nutmeg], and [salt] until smooth. This rich custard is what transforms the bread into something magical.
Slowly pour the custard evenly over the bread. Gently press down so each slice absorbs the mixture. This is the step where my daughter loves to “pat the bread goodnight” before it chills.
Cover the dish tightly with plastic wrap and refrigerate for at least 8 hours. Overnight soaking creates that classic crème brûlée texture.
In the morning, preheat the oven to 350°F. Remove the plastic wrap and bake for 35–40 minutes, until golden and set.
Allow the casserole to cool for 5 minutes. Flip pieces over as you plate so the caramelized bottom becomes the star. Serve with berries or whipped cream if you like, Olivia insists it’s “non-negotiable.”