I still remember the first time I made this French toast casserole for a weekend brunch — the kitchen smelled like warm cinnamon and vanilla, and everyone came back for seconds. This dish is a hands-off, crowd-friendly bake that turns day-old challah or brioche into custardy, caramelized slices with a crunchy oat crumble on top. If you like sweet, easy brunches that can be prepped ahead, this hits all the right notes. For a fun single-serve companion to the casserole, try these Cinnamon Roll French Toast Bites for a bite-sized take on similar flavors.
Why you’ll love this dish
This casserole brings together comfort and convenience. It soaks bread in a sweet spiced custard and bakes to a soft, set interior with a crunchy brown-sugar oat topping. Make it for leisurely weekend brunches, a holiday morning, or when you need an easy dish that feeds a crowd with minimal hands-on time. It’s budget-friendly because it rescues day-old bread, and kid-approved thanks to familiar flavors like cinnamon and vanilla.
"A perfect weekend recipe: custardy inside, crunchy on top, and simple enough to prep the night before."
The cooking process explained
Overview: Cube day-old bread, whisk a custard, pour it over the bread and let it soak. Make a quick oat and brown-sugar crumble, scatter it on top, then bake until golden and set. The whole bake takes about 30 to 40 minutes in the oven, plus resting. You can prep the night before and bake in the morning for an effortless brunch service.
What you’ll need
- 1 loaf bread (preferably challah or brioche, day-old) — sturdy enriched breads hold custard best.
- 4 large eggs
- 2 cups milk (whole milk or a non-dairy milk like oat or almond)
- 1/2 cup granulated sugar
- 1 teaspoon vanilla extract
- 1 teaspoon ground cinnamon
- 1/4 teaspoon ground nutmeg
- 1/4 cup chopped nuts (optional; walnuts or pecans)
- 1/2 cup brown sugar
- 1/2 cup old-fashioned oats
- 1/4 cup all-purpose flour
- 1/4 cup unsalted butter (cold, cubed)
Notes: For a richer custard use whole milk or half-and-half. For dairy-free, use full-fat oat or soy milk and vegan butter for the topping. If you prefer less sugar, reduce granulated sugar by 2 tablespoons.
Directions to follow
- Preheat the oven to 350°F (175°C). Grease a 9×13-inch baking dish.
- Cut the loaf into 1-inch cubes. Spread them evenly in the prepared dish.
- In a bowl, whisk together the eggs, milk, granulated sugar, vanilla, cinnamon, and nutmeg until smooth.
- Pour the custard over the bread cubes. Gently press the bread so it soaks up the liquid. Let the dish sit for 10 to 30 minutes so the custard penetrates the bread.
- Meanwhile, mix the brown sugar, oats, flour, and nuts in a separate bowl. Add the cold cubed butter and rub with your fingers until the mixture forms a coarse, crumbly topping.
- Sprinkle the crumble evenly over the soaked bread.
- Bake for 30 to 40 minutes, until the topping is golden and the center is set. A knife inserted in the center should come out mostly clean or the internal temperature should reach about 160°F.
- Let the casserole rest for 5 minutes before serving warm with maple syrup, fresh fruit, or a dusting of powdered sugar.
What to serve it with
This casserole shines on its own but pairs beautifully with bright, fresh sides. Serve with a bowl of mixed berries or slices of citrus to cut the sweetness. Yogurt or whipped cream on the side adds creaminess without extra fuss. For a brunch spread, include a platter of sliced fruit, roasted potatoes, and coffee or tea. If you want a playful complement, add a small plate of our Cinnamon Roll French Toast Bites for guests who want a sweeter, portable option.
How to store & freeze
Cool leftovers to room temperature, then refrigerate in an airtight container for up to 4 days. Reheat individual portions in the microwave for 30 to 60 seconds or warm slices in a 350°F oven for 10 to 15 minutes until heated through. To freeze, wrap the cooled casserole tightly with plastic wrap and a layer of foil, or transfer portions to freezer-safe containers. Freeze up to 2 months. Thaw overnight in the refrigerator, then reheat as directed. Always refrigerate within two hours of baking for food safety.
Pro chef tips
- Use day-old bread that’s slightly dry; it will absorb custard without turning mushy.
- Press the bread gently after pouring the custard to ensure even soaking.
- Keep the butter for the topping cold; rubbing it into the dry ingredients creates a better crumble.
- Bake until the center is set but still slightly soft — the casserole will continue to firm as it rests.
- If the topping browns too quickly, tent loosely with foil for the last 10 minutes of baking.
Flavor swaps
- Fruit-forward: Fold 1 to 1 1/2 cups chopped apples or pears into the bread before adding the crumble. Toss fruit with a little lemon juice to keep it bright.
- Nut-free: Omit nuts and add an extra 1/4 cup oats for texture.
- Gluten-free: Use gluten-free bread and a GF oat blend; substitute GF all-purpose flour in the topping.
- Maple brown-sugar: Replace half the brown sugar with pure maple syrup in the topping and add 1/4 teaspoon maple extract to the custard.
Common questions
How long does it take to prep and bake?
Active prep is about 15 to 20 minutes. Allow 10 to 30 minutes for the bread to soak, then bake 30 to 40 minutes. Total time depends on soak length and oven performance.
Can I assemble this the night before?
Yes. Assemble in the baking dish, cover, and refrigerate overnight. Let it sit at room temperature for 15 to 20 minutes before baking, then bake as directed.
What bread works best?
Enriched breads like challah or brioche are ideal because they have a tender crumb and absorb custard without falling apart. Sturdy sandwich bread or sourdough also work if day-old.
Is it safe to use raw eggs in the custard?
Baking the casserole until the center reaches about 160°F ensures the eggs are cooked. If you are concerned about raw eggs, you can use pasteurized eggs or bake until the center is fully set.
Can I make this dairy-free or vegan?
For dairy-free, use plant-based milk and vegan butter. For a vegan egg-free version, experiment with a tofu or chickpea-flour custard, but expect a different texture; test a small batch first.
If you’d like, I can also create a printable recipe card or scale this for a smaller crowd.
French Toast Casserole
Ingredients
Method
- Preheat the oven to 350°F (175°C). Grease a 9×13-inch baking dish.
- Cut the loaf into 1-inch cubes and spread them evenly in the prepared dish.
- In a bowl, whisk together the eggs, milk, granulated sugar, vanilla, cinnamon, and nutmeg until smooth.
- Pour the custard over the bread cubes, pressing gently to ensure even soaking. Let sit for 10 to 30 minutes.
- In a separate bowl, mix the brown sugar, oats, flour, and optional nuts.
- Add the cold cubed butter and rub it into the mixture until a coarse crumble forms.
- Sprinkle the crumble topping evenly over the soaked bread.
- Bake for 30 to 40 minutes until the topping is golden and the center is set.
- Let the casserole rest for 5 minutes before serving warm with maple syrup, fresh fruit, or powdered sugar.
