Blueberry & French Toast Casserole
A make-ahead blueberry French toast casserole that combines crusty bread, sweet blueberries, and a rich egg custard topped with a buttery streusel. Perfect for brunches, holidays, or weekday breakfasts, this dish is flavorful, satisfying, and easy to prepare in advance.
Equipment
- 1 x 9x13-inch baking dish
- 1 x Medium mixing bowl
- 1 x Large mixing bowl
- 1 x Whisk
- 1 × Pastry blender or fork
- 1 × knife (for cubing bread)
Ingredients
Base Casserole
- 1 loaf 12–14 oz / 340–400 g French bread, sourdough, brioche, or challah
- 1 cup 140 g fresh or frozen blueberries
- 8 large eggs
- 2 ¼ cups 540 ml whole milk
- ½ teaspoon ground cinnamon
- ¾ cup 150 g light brown sugar, packed
- 1 tablespoon 15 ml pure vanilla extract
Streusel Topping
- ⅓ cup 69 g packed brown sugar (light or dark)
- ⅓ cup 41 g all-purpose flour (spooned and leveled)
- ½ teaspoon ground cinnamon
- 6 tablespoons 85 g unsalted butter, cold and cubed
Optional Garnishes
- Extra blueberries
- Maple syrup
- Confectioners’ sugar
Instructions
- Prepare the Baking Dish: Start by greasing a 9×13-inch baking dish generously with unsalted butter or a light coat of nonstick spray. This step ensures that the casserole lifts out easily after baking and prevents any bread or custard from sticking to the edges. Place the dish on a flat, heat-safe surface where you can assemble everything with ease.
- Cube and Arrange the Bread: Take your loaf of French bread, challah, brioche, or sourdough and slice it into thick slices about 1 inch wide. Then, cut those slices into bite-sized cubes—roughly 1 inch in size. Transfer the bread cubes into the prepared baking dish, spreading them into an even layer so the custard will soak in evenly. Scatter the blueberries across the bread, tucking some between the cubes so every bite gets a pop of fruit.
- Whisk the Custard Mixture: In a large mixing bowl, crack in the eggs and whisk until the yolks and whites are fully combined. Gradually add the milk, whisking continuously to incorporate. Sprinkle in the ground cinnamon, followed by the brown sugar, making sure to break up any lumps so the sweetness is evenly distributed. Finally, stir in the vanilla extract. The result should be a smooth, fragrant custard mixture that will soak into the bread.
- Soak the Bread with Custard: Slowly pour the prepared custard over the bread and blueberry mixture in the baking dish. Make sure every piece of bread is moistened, pressing down gently with the back of a spoon or spatula if needed to help the bread absorb the liquid. Cover the dish tightly with plastic wrap or aluminum foil. Place it in the refrigerator to chill for at least 3 hours, though overnight resting (8–12 hours) is highly recommended for the richest flavor and texture.
- Preheat the Oven: When you’re ready to bake, remove the dish from the refrigerator and let it rest at room temperature for about 10 minutes while you preheat the oven. Set your oven to 350°F (177°C). This short rest helps prevent the cold dish from going straight into the hot oven, which can cause uneven baking.
- Mix the Streusel Topping: In a medium-sized mixing bowl, combine the brown sugar, all-purpose flour, and ground cinnamon. Stir until well blended. Add the cold, cubed butter to the bowl. Using a pastry blender, two forks, or your fingertips, cut the butter into the dry ingredients until you have a crumbly mixture with pea-sized pieces of butter. This topping will bake into a crunchy, golden-brown layer over the custard-soaked bread.
- Top the Casserole Generously: Uncover the chilled bread mixture and sprinkle the streusel topping evenly over the surface. Be sure to cover as much of the bread as possible with the buttery crumbs, as this will create a delightful contrast between the soft interior and the crisp, golden crust.
- Bake to Perfection: Slide the casserole into the preheated oven and bake for 45 to 55 minutes. For a softer, bread-pudding-like texture, remove the casserole closer to the 45-minute mark. If you prefer a firmer, more set texture with a deeper golden crust, extend the baking time up to 55 minutes. You’ll know it’s ready when the top is golden-brown and the custard is cooked through in the center.
- Cool Briefly Before Serving: Once baked, remove the casserole from the oven and let it sit for 5 to 10 minutes before slicing. This brief resting time allows the custard to settle, making it easier to serve neat squares or spoonfuls without falling apart.
- Serve and Garnish Creatively: Scoop or slice the casserole onto plates while still warm. For an extra touch, dust with confectioners’ sugar, drizzle with maple syrup, and scatter a few fresh blueberries on top. Serve immediately and enjoy a cozy, satisfying breakfast or brunch that feels indulgent yet balanced.
Notes
- Day-old or slightly stale bread works best, as it absorbs the custard beautifully without becoming mushy.
- Fresh or frozen blueberries can be used—if frozen, no need to thaw before adding.
- Resting overnight in the refrigerator ensures a richer flavor and more custard-like texture.
- Streusel topping can be prepared in advance and refrigerated until ready to use.
- Adjust baking time depending on whether you prefer a softer or firmer texture.
- This recipe can be halved easily for smaller gatherings.
- Variations are endless—try swapping blueberries with raspberries, apples, or pears for a seasonal twist.
