Step 1: Prepare the Bread

1. Cut the brioche or challah bread into thick slices, about 1 inch.
2. In a greased 9×13-inch baking dish, arrange the slices of bread in a single layer, overlapping slightly if needed.

Step 2: Make the Custard Mixture

1. In a large mixing bowl, whisk together the eggs, heavy cream, whole milk, granulated sugar, vanilla extract, ground cinnamon, and a pinch of salt until well combined.
2. Pour the custard mixture evenly over the bread slices, making sure all pieces are soaked. Press down gently so the bread absorbs the mixture.

Step 3: Refrigerate Overnight

1. Cover the baking dish with plastic wrap or aluminum foil and refrigerate overnight, or for at least 4 hours, to allow the bread to soak up the custard.

Step 4: Bake

1. Preheat the oven to 350°F (175°C).
2. Remove the cover from the baking dish and bake for 45–50 minutes, or until the top is golden brown and the custard is set.

Step 5: Caramelize the Sugar

1. Remove the French toast from the oven and let it cool slightly.
2. Evenly sprinkle the 1/4 cup granulated sugar over the top.
3. Use a kitchen torch to caramelize the sugar until it melts and turns golden brown. Alternatively, place it under a broiler for a few minutes, watching closely to avoid burning.

Step 6: Serve

1. Let the caramelized sugar cool for about a minute to harden.
2. Garnish with fresh berries and a dusting of powdered sugar if desired.
3. Serve warm and enjoy the Overnight Crème Brûlée French Toast.