Healthy Overnight French Toast Casserole

If you ask me, overnight French toast casserole is the smartest breakfast invention ever.

This make-ahead breakfast favorite turns regular bread into something magical while you sleep. Soft, custardy pieces of bread soak up a rich mixture of eggs, milk, and cinnamon overnight in your fridge.

Pop it in the oven the next morning, and your kitchen fills with the warm scent of vanilla and spices. A sprinkle of powdered sugar and a drizzle of maple syrup are all you need to finish it off.

It’s a no-fuss breakfast that feels special enough for holidays but easy enough for any weekend morning.

What Kind of Brioche Should I Use?

For French toast casserole, you’ll want to start with a good quality brioche bread – either from your local bakery or the bakery section of your grocery store. Day-old brioche actually works better than fresh since slightly stale bread soaks up more of the custard mixture without falling apart. If you can only find fresh brioche, just cut it into cubes and let it sit out for a few hours to dry out a bit. Regular brioche, chocolate brioche, or even challah bread can work well in this recipe – just make sure to avoid pre-sliced bread since you’ll want to cut thicker cubes yourself. If your local store doesn’t carry brioche, Hawaiian sweet bread makes a nice substitute.

Options for Substitutions

This breakfast casserole is pretty forgiving when it comes to substitutions. Here’s what you can swap:

• Brioche bread: While brioche gives the best rich, buttery result, you can use challah, French bread, or even regular white bread. Just make sure it’s slightly stale or dried out for better absorption of the custard.
• Whole milk and heavy cream: You can use all whole milk instead of the cream/milk combo, or try half-and-half for the entire liquid amount. For a dairy-free version, unsweetened almond or oat milk works, though the result won’t be quite as rich.
• Light brown sugar: Dark brown sugar works just fine, or try coconut sugar for a different flavor. Regular white sugar is okay too, though you’ll miss some of that caramel note.
• Vanilla essence: Vanilla extract, vanilla bean paste, or even a splash of bourbon can work here. You could also try almond extract for a different flavor (use just 1/2 teaspoon as it’s stronger).
• Maple syrup: While real maple syrup is recommended, you can serve this with honey, fruit compote, or your favorite breakfast syrup.

Watch Out for These Mistakes While Baking

The biggest challenge when making overnight French toast casserole is getting the bread-to-custard ratio right – using too much liquid can leave you with a soggy center, while too little results in dry, tough spots. For perfect results, make sure your bread cubes are about 1-inch in size and spread them evenly in the baking dish. Another common mistake is using fresh brioche, which can turn mushy – instead, leave your bread cubes out for a few hours to dry slightly, helping them better absorb the custard mixture without falling apart. Temperature matters too: using cold ingredients straight from the fridge can cause uneven baking, so remember to bring your eggs, milk, and cream to room temperature before mixing. For the best texture, press down gently on the bread pieces when pouring the custard mixture to ensure even soaking, and don’t skip the overnight rest – this crucial step allows the flavors to meld and the bread to fully absorb the custard.

What to Serve With French Toast Casserole?

This sweet and cozy breakfast casserole pairs perfectly with some savory sides to balance out the meal. I love serving it with crispy bacon or breakfast sausage links, which add a nice salty contrast to the sweet brioche and maple syrup. Fresh fruit is another great addition – try a bowl of mixed berries or sliced peaches in summer, or caramelized apples in fall. For a complete brunch spread, add a pitcher of cold orange juice or a pot of hot coffee to help cut through the richness of the casserole.

Storage Instructions

Make Ahead: This overnight French toast casserole is perfect for planning ahead! Assemble everything the night before, cover with plastic wrap, and let it hang out in the fridge overnight. The bread soaks up all those yummy flavors, making breakfast prep super easy the next morning.

Keep Fresh: Got leftovers? No problem! Cover the casserole with foil or transfer to an airtight container and pop it in the fridge. It’ll stay good for up to 3 days, though it’s usually best within the first 2 days while the texture is still perfect.

Warm Up: When you’re ready for round two, warm individual portions in the microwave for about 30-45 seconds. For bigger portions, cover with foil and heat in a 350°F oven for about 10-15 minutes. Add a fresh drizzle of maple syrup, and it’ll taste almost as good as when it first came out of the oven!

Preparation Time	20-30 minutes
Cooking Time	45-55 minutes
Total Time	65-85 minutes
Level of Difficulty	Medium

Estimated Nutrition

Estimated nutrition for the whole recipe (without optional ingredients):

• Calories: 3800-4200
• Protein: 80-90 g
• Fat: 200-220 g
• Carbohydrates: 500-550 g

Ingredients

• 1 loaf (16 ounces) brioche bread, cubed
• 8 large eggs, at room temperature, and beaten
• 2 cups whole milk (490 grams), at room temperature
• 1/2 cup heavy cream (119 grams), at room temperature
• 3/4 cup light brown sugar (150 grams), firmly packed
• 2 teaspoons vanilla essence
• 1 teaspoon ground cinnamon
• 1/2 teaspoon kosher salt
• 1/2 cup all-purpose flour (62.5 grams)
• 1/2 cup light brown sugar (100 grams), firmly packed
• 1 teaspoon ground cinnamon
• 1/4 teaspoon kosher salt
• 1/2 cup unsalted butter (113 grams, 1 stick), melted
• Powdered sugar, for garnish
• Pure maple syrup, for serving

Step 1: Prepare the Baking Dish and Bread

Begin by spraying a 9×13-inch baking dish with nonstick cooking spray to prevent sticking.

Add the bread cubes to the dish, spreading them out in an even layer.

Once done, set the dish aside for later.

Step 2: Make the Egg Mixture

In a large bowl, whisk together the eggs, milk, heavy cream, brown sugar, vanilla, cinnamon, and salt until the mixture is smooth and fully combined.

Pour this egg mixture evenly over the bread cubes in the prepared baking dish, gently pressing down to make sure all of the bread is soaked with the mixture.

Cover the dish tightly with plastic wrap and refrigerate it for at least 4 hours, or up to overnight, to allow the flavors to meld together.

Step 3: Prepare the Topping

In a medium bowl, whisk together the flour, brown sugar, cinnamon, and kosher salt to create the topping mixture.

Add the melted butter and mix until the topping becomes crumbly and well combined.

Once prepared, cover the topping mixture and refrigerate it until you are ready to bake the casserole.

Step 4: Assemble and Bake the Casserole

When you’re ready to bake, preheat your oven to 350°F (175°C).

Remove the casserole from the refrigerator and take off the plastic wrap.

Sprinkle the prepared topping evenly over the soaked bread cubes.

Bake the casserole uncovered in the preheated oven for 45-55 minutes, or until the top is golden brown and the center is set.

Step 5: Serve and Enjoy

Once baking is complete, let the casserole rest for 10 minutes to cool slightly and set further.

Before serving, dust with confectioners’ sugar and drizzle with maple syrup for added sweetness and flavor.

Enjoy your delicious and comforting breakfast casserole!