Want French toast without the fuss? Try this easy Overnight French Toast Casserole topped with a sweet, buttery streusel. Prep it the night before, bake the next morning, and enjoy a flavorful breakfast with minimal effort.

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Why does breakfast feel so chaotic during the school year?
On weekends I enjoy making everything from banana pancakes and glazed donut muffins to cinnamon coffee cake. But when Monday morning arrives, getting out the door often means a bowl of cereal for my daughter Elle while I grab another cup of coffee.
With mornings feeling different this year, I’m relying on make-ahead breakfasts that hold up through the week. Overnight French Toast Casserole is exactly that: easy to prepare for a weekend brunch and convenient as weekday leftovers.

What is overnight french toast?
Overnight French toast is essentially French toast transformed into a casserole—a breakfast-style bread pudding. You assemble it the night before, let the bread soak in a custard in the refrigerator, then bake it the next morning.

Two advantages of preparing the casserole ahead of time:
- The bread soaks up the custard fully, avoiding dry spots after baking.
- In the morning you only need to add the topping and bake—no extra prep required.
Simple and reliable.

The best bread for overnight french toast
Not all breads are created equal for this dish. I strongly prefer richer breads—brioche or challah—for their buttery, tender crumb. Sourdough or standard French bread can be too dry for this custardy bake.

Use brioche or challah for the best texture and flavor. Their richness complements the custard and creates a moist, flavorful casserole.

How to make overnight french toast casserole
This recipe has two main components: a custard-soaked bread base and a buttery cinnamon-oat streusel topping.
Start by cutting about a 1-pound loaf of brioche or challah into 1-inch cubes and place them in a greased 13×9-inch baking dish.

Whisk together the custard: eggs, whole milk, melted and cooled unsalted butter, sugar, vanilla, a touch of cinnamon, and a pinch of salt. Because traditional French toast is cooked in butter, adding some melted butter to the custard boosts that familiar buttery flavor.
Pour the custard evenly over the bread cubes, cover the dish, and refrigerate to let the bread absorb the mixture.

For the streusel, combine flour, brown sugar, cinnamon, salt, and cold cubed butter, then use a pastry blender or two forks to cut the butter into the dry ingredients until small clumps form. Stir in rolled oats, store the topping in a sealed container, and refrigerate until ready to bake.
The next morning, preheat the oven, sprinkle the chilled streusel over the casserole, and bake until golden and set. Serve warm with maple syrup and extra butter.

Optional: top with homemade whipped cream for an extra-special touch. For leftovers, portion into airtight containers and refrigerate—30–60 seconds in the microwave warms a single serving quickly for busy mornings.

Does this casserole have to sit overnight?
Although it’s called Overnight French Toast Casserole, it doesn’t strictly need overnight chilling. The casserole should rest for at least 4 hours to allow the custard to penetrate the bread, so you can assemble it in the morning and bake later the same day if needed. You can also prepare it on Sunday evening and bake that night or the next morning for weekday breakfasts.

Whether you let it sit overnight or for just a few hours, this casserole is a dependable breakfast you’ll return to again and again.

Overnight French Toast Casserole

Equipment
-
13×9-inch baking dish
Ingredients
For the French Toast:
- 1 loaf brioche (about 1 lb)
- 8 whole eggs
- 1 cup whole milk
- 4 tablespoons unsalted butter, melted and cooled
- 1 tablespoon pure vanilla extract
- ½ cup packed light brown sugar
- ½ teaspoon ground cinnamon
- Pinch of salt
For the Topping:
- ½ cup all-purpose flour
- ⅓ cup packed light brown sugar
- ½ teaspoon ground cinnamon
- Pinch of salt
- ½ cup cold unsalted butter, cubed
- ⅓ cup rolled oats
- Maple syrup and additional butter for serving
Instructions
- Butter or spray a 9×13-inch casserole dish with cooking spray.
- Cut the brioche into 1-inch cubes and place them in the prepared pan.
- In a large bowl, whisk the eggs until well beaten. Add the milk, melted butter, vanilla, cinnamon, salt, and brown sugar. Whisk until combined.
- Pour the egg mixture evenly over the brioche cubes. Gently stir any dry areas, but avoid overmixing. Cover and refrigerate for at least 4 hours or overnight (up to 12 hours).
- Prepare the topping: In a bowl, stir together flour, brown sugar, cinnamon, and salt. Use a pastry blender or two forks to cut the cold butter into the dry ingredients until small clumps form. Stir in the oats. Place the topping in a sealed container and refrigerate until ready to bake.
- When ready, preheat the oven to 350°F. Remove plastic wrap from the casserole and evenly sprinkle the chilled topping over the casserole.
- Bake for 50–60 minutes, or until the top is golden brown and the casserole is set.
- Serve warm with butter and maple syrup.
Nutrition
Nutrition information is automatically calculated and should be used as an approximation.