Overnight French Toast Casserole (Easy Make-Ahead Recipe)sta

The inspiration for this overnight French toast casserole comes from a version my mother-in-law makes every year for Thanksgiving and Christmas morning. It’s the kind of recipe that feels indulgent and cozy, but my version is a little lighter while still keeping all the classic flavor and texture.

It’s one of those breakfasts that works just as well for holiday mornings as it does for slow weekends when I want something comforting without a lot of effort. Most of the prep happens the night before, so in the morning all I have to do is pop it in the oven and let it bake until golden and set!

What Makes This Recipe Great

Here’s why this baked French toast casserole has earned a spot in my regular rotation:

• Make-ahead friendly: Prep everything the night before, so all that’s left to do in the morning is bake and serve.
• A lighter take on a classic: I use Greek yogurt instead of heavy cream and white whole wheat flour instead of all-purpose flour for a slightly healthier French toast casserole.
• Perfect for holidays or hosting: This is one of my favorite breakfast recipes to feed a crowd, and it feels special enough for Christmas morning or a nice brunch.
• Customizable: Swap the bread, nuts, or spices based on your preferences or what you have on hand.

What goes into this French toast casserole recipe is pretty simple, but a couple of thoughtful ingredient choices make it feel a bit lighter:

• Sourdough bread: Sourdough holds up really well overnight and gives you that perfect balance of soft inside and slightly chewy edges. A bakery-style loaf is ideal, but sandwich sourdough works, too. Thanks to the overnight soak, you don’t need to use stale bread. In a pinch, brioche, challah, French bread, or even whole wheat bread works. 
• Eggs: These add structure and that Classic French Toast “custard” feel. They also add a nice boost of protein, making this breakfast more filling.
• Full-fat Greek yogurt: This is one of my favorite swaps in this recipe. It adds creaminess and richness without the need for heavy cream or half and half, and bumps up the protein. It also gives the bake a slightly tangy depth.
• Milk (any kind): I usually use whatever I have on hand. This helps loosen the custard and keeps the texture soft. Whole milk, almond milk, and oat milk all work, and plant-based fortified options still add some calcium. 
• Maple syrup: This goes into the custard for sweetness and that classic French toast flavor. I still use light brown sugar (or coconut sugar) in the streusel topping for the right texture and crunch.
• Spices: Warming spices like cinnamon and nutmeg add flavor and pair perfectly with the maple syrup. Cinnamon fans, try my Cinnamon French Toast Bake or Instant Pot French Toast Casserole next.
• White whole wheat flour: I like using white whole wheat for a slightly more wholesome topping, but all-purpose flour can work, too.
• Pecans: These add crunch, especially in the streusel. Walnuts are an easy swap, or leave the nuts out entirely if you want.
• Butter: I usually use softened unsalted butter so it mixes into a crumble instead of a paste. Coconut oil can work, too, but I like the flavor and texture of butter in this one.
• Salt: Don’t skip this. A small amount helps balance the sweetness and brings out all the other flavors.

Try adding a teaspoon of vanilla extract to this breakfast casserole for added flavor and warmth!

This overnight French toast casserole comes together in a few simple steps, and most of the work happens the night before. I like it because once it’s assembled, the oven does the rest of the work in the morning for a delicious make-ahead breakfast.

Prep the Casserole (Night Before)

Cut the sourdough into bite-sized bread cubes, about 1-1 ½ inches each. If the loaf is fresh from the bakery, I sometimes just tear it apart with my hands for a more rustic texture.

From there, I spread the bread into a greased casserole dish and sprinkle in the chopped pecans, distributing them throughout.

In a large bowl, I whisk together the eggs, Greek yogurt, maple syrup, milk, cinnamon, nutmeg, and salt until smooth and fully combined. Then I pour the mixture evenly over the bread. At this point, I press the bread down gently with my hands to make sure every piece gets coated and starts soaking up the custard.

Once everything is assembled, I cover the baking dish tightly with plastic wrap and refrigerate it overnight.

Let It Soak

The resting time is what gives this sourdough French toast bake its soft, custardy texture.

If you don’t want to let it sit overnight, I’ve also done a shorter version where I let it rest in the fridge for about 30 minutes before baking. Overnight gives the deepest flavor and best texture, but both options work.

Bake Until Golden & Set

I bake the casserole covered at 350ºF for about 30 minutes to let it set through without drying out.

While it’s baking, I mix the streusel topping by combining the flour, brown sugar, pecans, and softened butter until it forms a crumbly texture. I aim for a sandy, clumpy consistency rather than a paste so it bakes into a crispy topping.

After the initial bake, I remove the foil and sprinkle the streusel evenly over the top. Then I return it to the oven and bake for another 15 to 25 minutes, until the center sets and the top is golden brown and crisp.

It’s ready when the edges are lightly golden, the center no longer looks wet or jiggly, and a knife inserted in the middle comes out mostly clean with just a little moisture. Let it rest for 5 to 10 minutes before slicing so it holds its shape better when serving.

This French toast casserole is really flexible, so I like to adjust it depending on what I’m serving it for or what I have in the kitchen. Here are a few easy ways to switch it up:

• Berry variation: Add a handful of fresh or frozen berries (like blueberries or raspberries) into the bread mixture before baking for a fresh, slightly tart twist. They’ll add a little vitamin A, vitamin C, and potassium to your finished bake, too.
• Nut-free option: Skip the pecans entirely or replace them with extra bread for a simpler, allergy-friendly version that still bakes up beautifully.
• Bread swap: Swap sourdough for brioche or challah for a richer texture closer to bread pudding, or use whole wheat bread for a slightly heartier feel. Softer breads will result in a more custardy texture.
• Extra warm spice: Add a pinch of ground ginger or cardamom alongside the cinnamon and nutmeg for a deeper, more spiced flavor. 
• Lower sugar option: Reduce the brown sugar in the streusel slightly and lean more on cinnamon and vanilla for sweetness. You can still get that cinnamon sugar flavor.

Looking for more bakes for your next brunch? Try my English Muffin Breakfast Bake or my Egg and Croissant Breakfast Casserole for a savory option.

What are common mistakes when making overnight French toast casserole?

One of the biggest mistakes is not using enough time for the bread to absorb the custard, which can lead to an uneven texture. Another common issue is skipping the step of pressing the bread down into the custard, which helps everything soak evenly. Finally, overbaking can dry it out, so I always pull it once the center is just set and the top is golden.

Why is my French toast casserole soggy?

Sogginess usually comes from too much liquid or not enough structure in the bread. I find that using a sturdy bread, like sourdough, helps a lot because it holds up better during soaking. It’s also important to let it bake long enough so the center fully sets. If it still looks wet in the middle, I’ll loosely cover it with foil and give it a little more time in the oven.