French Toast Casserole Recipe

I turned day-old brioche into a French Toast Bundt Cake with a hidden custard center and one pantry spice that most recipes overlook.

I never expected a simple pile of cubed brioche or challah to start so many arguments at my breakfast table. One bite and the edges sing while the center stays almost custardy, which always makes people ask what I did different.

There is a twist that makes it feel fancy without trying hard, so I call it my secret not because it is complicated but because it surprised me. If you like a little spice, a dusting of cinnamon changes everything.

Fans of Easy French Toast Bake will nod, but this version keeps you guessing in the best possible way.

Ingredients

• Rich, buttery brioche or challah soaks up custard, gives tender cubes and slight sweetness.
• Eggs add protein and structure, make custardy center and help everything set.
• Milk and cream add calcium and fat, make texture creamy and rich.
• Unsalted butter gives flavor, browns streusel, and makes crust crisp and golden.
• Granulated sugar sweetens, brown adds molasses notes and moist deeper caramel flavor.
• Cinnamon and nutmeg are warm spices that add aroma, cozy flavor and hint of autumn.
• Pecans or walnuts add crunch, healthy fats and a toasty, slightly bitter contrast.

Ingredient Quantities

• 1 (1 pound) loaf brioche or challah cut into 1 inch cubes about 10 to 12 cups
• 8 large eggs
• 2 cups whole milk
• 1 cup heavy cream
• 1/2 cup granulated sugar
• 2 teaspoons pure vanilla extract
• 2 teaspoons ground cinnamon
• 1/4 teaspoon ground nutmeg
• 1/2 teaspoon fine salt
• 8 tablespoons unsalted butter divided 4 tablespoons melted for custard and 4 tablespoons cold for streusel
• 1/2 cup packed light brown sugar
• 1/2 cup all purpose flour
• 1/2 to 3/4 cup chopped pecans or walnuts optional
• Maple syrup for serving optional
• Powdered sugar for dusting optional

How to Make this

1. Preheat oven to 350°F and butter a 9×13 inch baking dish or a large cast iron skillet; cut the brioche or challah into 1 inch cubes (about 10 to 12 cups) and spread them evenly in the dish, stale bread works best.

2. In a large bowl whisk together 8 large eggs, 2 cups whole milk, 1 cup heavy cream, 1/2 cup granulated sugar, 2 teaspoons pure vanilla extract, 2 teaspoons ground cinnamon, 1/4 teaspoon ground nutmeg, 1/2 teaspoon fine salt and 4 tablespoons melted unsalted butter until smooth.

3. Pour the custard evenly over the bread, press down gently so most cubes get soaked, poke the top with a spatula so the liquid penetrates. Let it sit 20 to 30 minutes at room temp or cover and refrigerate overnight (up to 24 hours) for a more custardy center.

4. While the bread soaks make the streusel: in a bowl mix 1/2 cup packed light brown sugar and 1/2 cup all purpose flour and 1/2 to 3/4 cup chopped pecans or walnuts if using, then cut in 4 tablespoons cold unsalted butter (cubed) with a fork or pastry cutter until you have coarse crumbs.

5. Sprinkle the streusel evenly over the soaked bread, pressing a little so it adheres but keeping some crumb texture on top.

6. Bake uncovered at 350°F for about 45 to 55 minutes until the top is golden and a knife inserted in the center comes out mostly clean with a few moist crumbs; if it’s browning too fast tent loosely with foil for the last 10 to 15 minutes.

7. Remove from oven and let rest 10 to 15 minutes so the custard finishes setting; this makes for cleaner squares when you serve it.

8. Serve warm with maple syrup and a dusting of powdered sugar if you like, extra chopped nuts on top is nice too.

9. Leftovers can be covered and refrigerated up to 3 days; reheat portions in a 350°F oven for 10 to 15 minutes or microwave individual pieces until warm.

10. Quick hacks: use a 1 pound loaf for the right ratio, cut the cubes slightly smaller if you like it more custardy, and dont skip the cold butter in the streusel or you’ll lose that crumbly topping texture.

Equipment Needed

1. 9×13 inch baking dish or a large cast iron skillet
2. Large mixing bowl
3. Whisk
4. Measuring cups and spoons (liquid and dry)
5. Sharp knife and cutting board
6. Rubber or silicone spatula (for pressing and poking)
7. Pastry cutter or fork (for the streusel)
8. Baking sheet and aluminum foil (for tenting if it browns too fast)
9. Oven mitts and a cooling rack, dont skip these

FAQ

French Toast Casserole Recipe Substitutions and Variations

• Bread (brioche or challah): If you dont have brioche, use day-old French baguette or a country sourdough cut into 1″ cubes; croissants also work for an extra buttery, flaky result. Same volume (10–12 cups). Baguette gives a chewier, more custardy texture, croissants make it richer.
• Dairy (2 cups whole milk + 1 cup heavy cream): Swap with 3 cups half-and-half for a slightly lighter, still creamy custard; or whisk 2 cups whole milk with 1 cup plain full-fat Greek yogurt for a tangier, more set bake. For dairy-free use 3 cups full-fat canned coconut milk (note the coconut flavor).
• Eggs (8 large): For egg-free/vegan versions use flax “eggs” (1 tablespoon flaxseed meal + 3 tablespoons water per egg, so multiply that by 8) or pureed silken tofu (about 1/4 cup per egg, so ~2 cups for 8). Flax gives a firmer, slightly gummy set, tofu gives a smooth custardy texture.
• Streusel butter (4 tablespoons cold): Use equal parts solid coconut oil or a plant-based stick margarine if you need it dairy-free; ghee works too if you want nuttier flavor. For nut allergies swap pecans/walnuts with toasted sunflower seeds or 1/2 cup rolled oats in the streusel, same volume.

Pro Tips

1. Let it soak overnight in the fridge if you can. That gives a custardy center and way better texture than a quick soak, and if you want it less set just cut the cubes a bit smaller so more custard soaks in.

2. Warm the milk and cream just until slightly warm to the touch, then slowly whisk them into the eggs so you dont scramble them. Warm liquid helps dissolve the sugar and lets the bread absorb the custard more evenly.

3. Keep the streusel butter cold and work it into the flour and sugar until you have coarse crumbs. Toast the nuts first for more flavor, then sprinkle the crumbs on top and gently press so some texture stays on the surface.

4. Watch the top near the end of baking and tent with foil if it gets too brown. Let the pudding rest about 10 to 15 minutes after you take it out so it finishes setting, you get cleaner slices and it reheats nicely.