This blueberry French toast casserole bakes up soft and custardy with a crunchy cinnamon sugar topping and juicy blueberries throughout, so every bite hits sweet and tart notes without sogginess. It is overnight friendly for low‑stress mornings and scales well for a crowd, with clear doneness cues and simple swaps if you are out of brioche or prefer dairy‑free milk.
Table of Contents
Ingredients
- 1 pound day‑old brioche or challah, cut in 1 inch cubes; enriched bread gives tender custard with structure.
- 1.5 cups fresh or frozen blueberries; no thaw needed for frozen to prevent streaking.
- 6 large eggs; the custard sets the casserole without being eggy when balanced with dairy.
- 2 cups whole milk or 1.5 cups milk plus 0.5 cup heavy cream for extra richness; fat helps prevent a rubbery set.
- 1/2 cup maple syrup or 1/3 cup sugar for a less sweet profile; maple adds moisture and flavor depth.
- 1 tablespoon vanilla extract for aroma that carries after baking.
- 1.5 teaspoons ground cinnamon for warm spice that complements blueberries.
- 1/4 teaspoon kosher salt to sharpen sweetness and balance dairy.
- 2 tablespoons unsalted butter, softened, to grease the dish and prevent sticking on edges.
- Streusel: 1/2 cup all‑purpose flour, 1/3 cup brown sugar, 1 teaspoon cinnamon, pinch of salt, 4 tablespoons cold butter cubed; keeps the top crisp and protects custard moisture.
- Optional lemon zest from 1 lemon to brighten the berries without souring the custard.
- Practical swaps: thick white sandwich bread in a pinch, olive oil instead of butter for greasing, and pomegranate molasses in place of part of maple for tangy depth.
How to Prepare Blueberry French Toast Casserole
- Prep the dish and bread 5 minutes: Grease a 9 by 13 inch baking dish with softened butter and scatter half the bread in an even layer so custard soaks uniformly without dense pockets.
- Layer berries 2 minutes: Sprinkle half the blueberries over the bread to distribute bursts of fruit instead of a wet bottom layer.
- Make custard 3 minutes: Whisk eggs, milk, maple, vanilla, cinnamon, salt, and lemon zest until no streaks of egg white remain so the set is even and not streaky.
- Assemble 2 minutes: Pour half the custard over bread, add remaining bread and berries, then pour the rest, gently pressing to dampen the top without compressing cubes which would reduce lift.
- Chill 30 minutes to overnight: Cover and refrigerate to hydrate the bread fully which prevents dry centers and overbaked edges later.
- Heat oven 10 minutes: Preheat to 350 degrees F and place a rack in the center for balanced browning.
- Make streusel 3 minutes: Rub flour, brown sugar, cinnamon, salt, and cold butter to pea size so it bakes into crisp nuggets, not a paste.
- Top and bake 45 to 55 minutes: Uncover casserole, scatter streusel, and bake until the top is deeply golden and the center jiggles slightly like set cheesecake with an internal temp around 175 to 180 F to avoid a wet custard.
- Rest 10 minutes: Let it stand so custard finishes setting and slices hold cleanly without weeping.
- Serve: Spoon warm with extra maple, yogurt, or a squeeze of lemon over each portion to balance sweetness.
Substitutions and variations
- Bread: Use sturdy white bread dried in a 300 degrees F oven for 8 to 10 minutes if brioche is unavailable to mimic day‑old texture and prevent mush.
- Dairy free: Use full‑fat oat milk or coconut milk and swap butter with olive oil to keep richness and browning.
- Blueberry lemon: Add 2 teaspoons lemon zest and a 1/2 teaspoon almond extract for a bakery note that complements berries.
- Cinnamon roll twist: Spread 2 tablespoons softened butter and 2 tablespoons brown sugar over half the bread cubes before layering for caramel pockets without sog.
- Savory‑sweet: Add a handful of diced smoked beef or pastırma for salty pops against the sweet custard for a brunch board feel.
Storage and reheating
- Storage: Cool completely then cover and refrigerate up to 3 days to maintain moisture and food safety.
- Reheat by slice: Microwave 45 to 60 seconds on medium power then finish in a 350 degrees F oven or toaster oven for 5 to 8 minutes to bring back crunch.
- Reheat whole: Cover loosely with foil and warm at 325 degrees F for 20 to 25 minutes until heated through without drying the top.
- Freeze: Wrap portions tightly and freeze up to 2 months and thaw overnight before reheating to preserve texture.
Most asked FAQs
- Can this be baked right away?
Yes, but a 30 minute soak improves custard absorption and prevents dry centers so the set is creamy edge to edge. - Fresh or frozen blueberries?
Both work well and do not thaw frozen berries to avoid streaky batter and excess liquid pooling at the bottom. - How do I prevent a soggy bottom?
Use day‑old or lightly dried bread and bake uncovered on the center rack until the middle barely jiggles, not sloshes which indicates underbaked custard. - Why did mine turn out eggy?
Too many eggs for the bread and dairy ratio or underseasoned custard can taste egg‑forward and balancing with dairy and vanilla plus proper bake time smooths flavor and texture. - Can I assemble two days ahead?
Yes, but add streusel just before baking and keep the dish tightly covered to prevent the top from drying out in the fridge.
Blueberry French Toast Casserole
This blueberry French toast casserole bakes up soft and custardy with a crunchy cinnamon sugar topping and juicy blueberries throughout, so every bite hits sweet and tart notes without sogginess. It is overnight friendly for low‑stress mornings and scales well for a crowd.
Equipment
- 9×13 inch baking dish
- Whisk
- Mixing bowls
Ingredients
- 1 pound day-old brioche or challah cut in 1 inch cubes
- 1.5 cups fresh or frozen blueberries no thaw needed for frozen
- 6 large eggs
- 2 cups whole milk or 1.5 cups milk plus 0.5 cup heavy cream
- 1/2 cup maple syrup or 1/3 cup sugar
- 1 tablespoon vanilla extract
- 1.5 teaspoons ground cinnamon
- 1/4 teaspoon kosher salt
- 2 tablespoons unsalted butter softened, for greasing
- 1 lemon zest optional
Streusel Topping
- 1/2 cup all-purpose flour
- 1/3 cup brown sugar
- 1 teaspoon cinnamon
- salt pinch
- 4 tablespoons cold butter cubed
Instructions
- Grease a 9 by 13 inch baking dish with softened butter and scatter half the bread in an even layer.
- Sprinkle half the blueberries over the bread.
- Whisk eggs, milk, maple syrup, vanilla, cinnamon, salt, and lemon zest (if using) until no streaks of egg white remain.
- Pour half the custard over bread, add remaining bread and berries, then pour the rest, gently pressing to dampen the top without compressing cubes.
- Cover and refrigerate for 30 minutes to overnight.
- Preheat oven to 350 degrees F and place a rack in the center.
- Rub together flour, brown sugar, cinnamon, salt, and cold butter to pea size for the streusel.
- Uncover casserole, scatter streusel on top, and bake for 45 to 55 minutes until the top is deeply golden and the center jiggles slightly with an internal temp around 175 to 180 F.
- Let stand for 10 minutes before serving.
- Serve warm with extra maple syrup, yogurt, or a squeeze of lemon.
Notes
Bread: Use sturdy white bread dried in a 300 degrees F oven for 8 to 10 minutes if brioche is unavailable. Dairy free: Use full-fat oat milk or coconut milk and swap butter with olive oil. Blueberry lemon: Add 2 teaspoons lemon zest and 1/2 teaspoon almond extract. Storage: Cool completely then cover and refrigerate up to 3 days. Reheat by slice in microwave 45 to 60 seconds then finish in 350 F oven for 5 to 8 minutes. Freeze portions up to 2 months.