Ingredients:
- 1 (1.5–2 lb) loaf Brioche or Challah Bread, preferably stale, cubed into 1-inch pieces
- 2 Tbsp Unsalted Butter, softened (for greasing)
- 8 large Eggs
- 1 cup Whole Milk
- 1 cup Heavy Cream (Double Cream)
- 1/2 cup Granulated Sugar
- 1/4 cup lightly packed Brown Sugar
- 2 tsp Pure Vanilla Extract
- 1 tsp Ground Cinnamon
- 1/4 tsp Ground Nutmeg
- 1/2 tsp fine sea Salt
- 1/2 cup All-Purpose Flour (for optional streusel)
- 1/4 cup packed Brown Sugar (for optional streusel)
- 1/2 tsp Ground Cinnamon (for optional streusel)
- 4 Tbsp (1/2 stick) cold Unsalted Butter, cubed (for optional streusel)
Instructions:
- Prep the Dish and Bread: Grease a 9x13 inch casserole dish generously with softened butter. Slice or cube the brioche into 1-inch pieces and arrange the bread evenly in the prepared dish, ensuring they are slightly overlapping.
- Make the Custard: In a large mixing bowl, whisk together the eggs, whole milk, heavy cream, granulated sugar, brown sugar, vanilla extract, cinnamon, nutmeg, and salt until completely uniform and slightly frothy.
- Soak and Chill: Pour the custard mixture slowly and evenly over the arranged bread. Press down gently to ensure all pieces are submerged and saturated. Cover the dish tightly and refrigerate for a minimum of 4 hours, but ideally overnight (8–12 hours).
- Prepare the Streusel (Optional): If using, combine the flour, brown sugar, and cinnamon in a small bowl. Cut in the cold butter using a pastry blender or your fingertips until the mixture resembles coarse crumbs. Keep refrigerated until ready to bake.
- Preheat and Rest: Preheat oven to 375°F (190°C). Remove the casserole from the fridge while the oven heats up (approx. 15 minutes).
- Top and Bake (Covered): If using streusel, sprinkle it evenly over the top. Cover the dish loosely with foil and bake for 30 minutes.
- Bake Final Phase (Uncovered): Remove the foil and bake for another 15–20 minutes, or until the top is golden brown and a knife inserted near the center comes out mostly clean. The internal temperature should register about 200°F (93°C).
- Rest and Serve: Let the casserole rest for 10 minutes after removing it from the oven before slicing and serving with your preferred toppings, like powdered sugar and maple syrup.