Soft and custardy on the inside with a crunchy oat topping, this blueberry overnight french toast bake makes brunch for a crowd! Prep it the night before so that the bread absorbs all the flavors; the next morning, simply pop it into the oven and bake it up.

As a non-morning person, I'm all about the brunch recipes that can be (mostly) made the night before. While we love a savory overnight breakfast casserole, sometimes a sweet option is just what the doctor ordered!

Just like it's name suggests, this overnight french toast bake can be assembled the night before. In fact- it's better when done this way, because the bread has time to properly absorb the liquids, infusing with cinnamon, nutmeg and vanilla flavors throughout. This results in a more flavorful french toast casserole with that perfect custardy texture.

Reasons you’ll ♡ this overnight french toast bake

you do the bulk of the work the night before- in the morning, simply pop it into the oven!
the textures are so good- soft on the inside, but with a crunchy oat topping
you can customize it with different flavors

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What is french toast casserole?

It is all the same flavors as traditional french toast, prepared slightly differently. We simply cut a loaf of bread into cubes and soak it with an egg/milk mixture overnight in a casserole dish. This recipe has bit of maple syrup to sweeten it slightly, some vanilla, cinnamon and nutmeg to give it a nice flavor, and frozen blueberries scattered all over it.

After pouring the liquid mixture over it, we cover the overnight french toast with plastic wrap and refrigerate it overnight. The bread infuses with the spices and absorbs the egg mixture, and is ready to bake up in the morning.

Turning french toast into a casserole makes this so much more hands off and means that no one has to stand over the stove flipping the toast. That way you can be free to visit with your guests, or get some other things done while the casserole bakes up.

Pick the right bread

Opt for a sturdy loaf of bread that is not too 'squishy'. If the bread is too soft, the casserole could end up soggy; we want the bread to be able to absorb the eggs and milk to produce a custard-like texture.

Great choices include

sourdough *my personal favorite
french bread
challah
brioche

Prepping the casserole

Bread

Stale bread works great for this casserole as it really holds its shape while soaking in the custard; consider buying your bread a day or two early. Cut the loaf into 1 inch cubes; you can also tear into rough, craggy pieces using your hands. Leave the crust on the bread; this adds color and added texture to the casserole.

Custard

Beat together eggs, milk, vanilla, cinnamon, nutmeg and maple syrup until completely combined. I've used 1% milk to keep this a little bit lighter, but for an even richer casserole, you could replace half the milk with half and half. If you are dairy-free, almond milk should work just fine.

Crunchy oat topping

To add crunchy texture to the top of the casserole, this oat topping does the trick. Stir together melted butter, maple syrup, cinnamon, rolled oats and a pinch of salt.

I do not recommend adding the oat topping the night before, as this will cause it to be soggy.

Assembly

Spray a 9 x 13 inch casserole dish with oil, then scatter half the bread cubes over. Scatter half of the blueberries, then repeat. Pour the egg mixture evenly over the casserole. Cover and refrigerate overnight.

The next morning, top with the oat topping, then you're ready to bake!

Flavor variations

add a bit of lemon zest to compliment the blueberries
add half a block of cream cheese cut into small cubes and scattered through the casserole
swap the blueberries for any berry: strawberries, blackberries, raspberries, cherries, you name it, they'd all be great!
swap the blueberries for chopped apple: I recommend 2 peeled and chopped apples
add some pecans, almonds or walnuts
swap the vanilla extract for almond extract (you'll want to reduce it by half as almond extract can have a very strong taste!)

Meal prep/storage

This recipe can be stored in the fridge for a few days, though it's important to know that the crunchy oat streusel will lose it's texture. Here's how to store it:

fridge- portion out cooled casserole into meal prep containers, or cover the casserole dish well. Refrigerate for up to 4 days.
reheat- heat in the microwave or (best) in a covered dish in the oven at 350°F for 10-15 minutes, or until warmed through
freezer- portion out into meal prep containers or wrap individual portions with plastic wrap and place in a larger container. Freeze for up to 1 month.
thaw- thaw in the fridge overnight before reheating.

Blueberry Overnight French Toast Bake