Overnight French Toast Casserole

This luscious overnight French toast casserole has bright lemon flavor, buttery brioche, sweet berries, and a light almond crunch. The golden top and pop of color look stunning on the table and taste even better on the plate.

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My top secret for stress-free mornings is prepping ahead, and this casserole leaves very little to do when the coffee's brewing. If you want another elegant but easy breakfast, my crustless quiche with cottage cheese packs a big protein punch in every light and fluffy bite.

What you need to make Overnight French Toast Casserole

Overnight French Toast Bake

• Brioche or challah bread. These soft breads soak up the lemony custard while keeping their texture. French bread can pinch hit in a bind. I do not recommend sandwich bread.
• Fresh raspberries. Raspberries are lovely here, but any in-season berries work. Blueberries and strawberries are especially good with lemon and almonds. Frozen berries are fine and do not need to be thawed first.
• Sliced almonds.
• Lemon. Fresh zest and juice wake up all the flavors.
• Eggs.
• Milk. For a richer result, try a mix of milk and half and half. Plant-based substitutes may be used.
• Plain Greek yogurt. The tang of Greek yogurt is a flavor booster, but plant-based substitutes may be used.
• Honey or maple syrup.
• Vanilla extract.
• Salt.
• Sugar. Raw sugar is pictured here, but white sugar works well.
• Powdered sugar.
• Not pictured: almond extract, non-stick cooking spray

Optional Garnishes (not pictured)

• Powdered sugar, for dusting
• Fresh raspberries tossed with sugar
• Whipped cream
• Raspberry jam (if substituting a different berry, use the corresponding jam flavor)

See recipe card for quantities.

How to make Overnight French Toast Casserole

Prep the lemon: Zest 1 lemon by rolling the lemon on the counter with pressure to release the juices then grating the zest into a bowl using a microplane grater. Set zest aside and juice the lemon. Set juice aside and discard pulp.

Prep the pan and bread: Prepare a 9x13 baking dish with non-stick cooking spray. Cut 1 loaf brioche or challah bread into 1" cubes.

Layer: Spread half the bread cubes evenly in the prepared dish (1). Scatter half of the fresh raspberries and half of the sliced almonds over the bread cubes (2).
Repeat with the remaining bread cubes, raspberries, and almonds (3).

Whisk the custard: In a large bowl, whisk together eggs, milk, plain Greek yogurt, honey or maple syrup, vanilla extract, almond extract, pinch salt, lemon juice, and lemon zest.

Soak: Pour the custard mixture evenly over the bread, raspberries, and almonds in the pan (4).

Press down on the bread slightly so it can soak up more of the egg mixture (5).

Cover the baking dish with aluminum foil or plastic wrap and refrigerate overnight. Store the remaining lemon juice and zest in covered containers in the fridge overnight.

Top and bake: In the morning, preheat the oven to 350ºF. Mix together 2 tablespoons sugar and 1 teaspoon lemon zest, and sprinkle the lemon sugar mixture and ¼ sliced almonds evenly over the casserole (6).

Bake uncovered at 350ºF for 40-45 minutes until puffed, golden, and set in the center (7).

Glaze: Make the glaze by combining ½ cup powdered sugar and 2 tablespoons of the reserved lemon juice. Drizzle evenly over the baked casserole (8).

Optional garnishes:

• Whipped cream
• Raspberry jam, or use a matching jam if you swapped berries
• Fresh raspberries tossed with a little sugar
• Extra powdered sugar for dusting

Make it your own

Whether you need to adjust for dietary restrictions or what is in season, this overnight French toast casserole recipe is flexible.

• Non-dairy - use plant-based substitutes for the milk and yogurt
• Gluten-free - use your favorite gluten-free loaf that is soft but sturdy enough not to get mushy
• Seasonal swaps - Try blueberries, strawberries, blackberries, or a mix.

Storage and freezing

Store & reheat: Refrigerate leftovers in an airtight container for up to 4 days. Reheat individual portions in the microwave.

Freeze: Freeze the baked casserole for up to 6 months. For easy single servings, slice before freezing. Thaw overnight in the refrigerator, or use the microwave defrost function, then reheat.

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