Ingredients:

  • 1 large loaf brioche or challah, day-old if possible — 10–12 cups cubed (about 1 lb / 450 g)
  • 8 large eggs
  • 2 cups whole milk (480 ml)
  • 1 cup heavy cream (240 ml) — or use 1 1/4 cups milk + 3/4 cup cream to lighten
  • 1/2 cup granulated sugar (100 g)
  • 2 teaspoons pure vanilla extract (10 ml)
  • 1 teaspoon ground cinnamon
  • 1/2 teaspoon fine sea salt
  • 2 tablespoons unsalted butter, melted (28 g) — to dot the top before baking
  • 1/2 cup packed light brown sugar (100 g)
  • 1/2 cup all-purpose flour (60 g)
  • 6 tablespoons cold unsalted butter, cubed (85 g)
  • 1/2 cup chopped pecans or walnuts (50 g) — optional but recommended
  • 1/2 teaspoon ground cinnamon (for streusel)
  • Pinch of salt (for streusel)
  • Warm maple syrup (for serving, optional)
  • Powdered sugar, for dusting (optional)
  • Fresh berries (optional)

Instructions:

  1. Prep the bread: Cut bread into roughly 1–1.5-inch cubes. Spread on a rimmed baking sheet and let sit uncovered for an hour to slightly dry, or use day-old bread. If in a hurry, toast cubes lightly in a 300°F (150°C) oven 8–10 minutes.
  2. Make the custard: Whisk eggs, milk, cream, granulated sugar, vanilla extract, ground cinnamon, and salt in a large bowl until homogeneous and slightly frothy.
  3. Assemble casserole: Place bread cubes into a greased 9x13-inch (23x33 cm) baking dish. Pour custard evenly over the bread, pressing gently so cubes absorb liquid. Dot the top with melted butter. Custard should come up to but not fully submerge the top layer; add a splash more milk if bread looks dry.
  4. Rest / chill: Cover and refrigerate for at least 4 hours or overnight for best results. If baking the same day, allow 30–60 minutes at room temperature for a partial soak.
  5. Make streusel: Combine packed light brown sugar, all-purpose flour, ground cinnamon, and a pinch of salt in a medium bowl. Cut in cold cubed butter until crumbly, then stir in chopped pecans or walnuts. Sprinkle streusel evenly over the soaked casserole before baking.
  6. Bake: Preheat oven to 350°F (175°C). Bake uncovered for 45–55 minutes or until casserole is set in the center and streusel is golden brown. Test doneness by inserting a sharp knife into the center — it should come out mostly clean with only moist crumbs; internal temperature should reach 160–165°F (71–74°C). If top browns too quickly, tent loosely with foil for the final 10–15 minutes.
  7. Rest & serve: Let rest 10–15 minutes before cutting to allow the custard to set. Serve warm with maple syrup, a dusting of powdered sugar, and fresh berries if desired.