This baked banana French toast casserole has become my go-to weekend breakfast and a holiday morning lifesaver. I discovered this combination one sleepy December when guests were arriving early and I wanted something I could assemble the night before. The casserole wakes up in the oven with a golden, slightly crisp top and a custardy interior that’s studded with tender banana pieces. It’s the kind of dish that draws everyone out of bed and keeps the coffee flowing.

What makes this version special is the balance between the creamy custard and the caramel notes from ripe bananas. Using day-old sourdough or French bread gives structure so the custard soaks in without turning mushy; the interior stays soft while the top crisps. I love that it’s mostly hands-off: a quick evening prep, overnight chill, and a short bake the next morning. It has saved me more than once when hosting brunch — guests always ask for the recipe.

Ingredients

• 1 lb sourdough or French bread: Use day-old bread for best texture. The slightly dry loaf soaks custard without dissolving; I prefer a country-style sourdough or baguette, torn into 1–2-inch chunks.
• 8 large eggs: Room temperature eggs help create a smoother custard. Extra-large eggs will make the custard richer; if using smaller eggs, add one more.
• 2 cups whole milk: Full-fat milk contributes to a silky texture; you can substitute 2% for a lighter result but expect a slightly less creamy interior.
• 1/2 cup heavy cream: Adds luxury and helps the baked custard hold its shape while staying tender.
• 1/2 cup sugar: Granulated sugar balances banana sweetness. Brown sugar could be swapped for a warmer note in the custard itself.
• 6–7 medium bananas, chopped: Use ripe bananas with brown flecks for the best aroma and sweetness. Chop into 1/2-inch pieces so they distribute evenly without collapsing into the custard.
• 3/4 cup all-purpose flour (streusel): For the topping; if you want a gluten-free option use 3/4 cup gluten-free blend.
• 1/2 cup salted butter (streusel): Cold butter cut into the flour yields a crumbly topping. Unsalted butter is fine — add a pinch of salt if using it.
• Optional flavorings: 1 teaspoon vanilla extract and 1 teaspoon ground cinnamon in the custard; consider a pinch of nutmeg for warmth.

Instructions

Prepare the dish: Grease a 9×13-inch casserole dish thoroughly with butter or nonstick spray so the custard won’t stick. Tear or cut 1 lb of day-old sourdough or French bread into 1–2-inch chunks and scatter them evenly in the prepared dish, creating a rough, airy bed that will soak up the custard. Make the custard: In a large bowl, whisk 8 large eggs until smooth. Add 2 cups whole milk, 1/2 cup heavy cream, 1/2 cup granulated sugar, 1 teaspoon vanilla extract, and 1 teaspoon ground cinnamon; whisk until fully combined and slightly frothy. The vanilla and cinnamon infuse the custard while the sugar helps with browning and flavor. Combine bread and bananas: Pour the custard evenly over the bread pieces and gently fold in 6–7 chopped medium bananas with a rubber spatula, taking care not to mash them. Press the bread down lightly so each piece contacts the custard — this encourages even soaking without becoming entirely mushy. Chill overnight: Cover the dish tightly with plastic wrap and refrigerate for at least 8 hours or overnight. This resting period lets the custard fully penetrate the bread, resulting in a cohesive, custardy interior rather than dry pockets. Bake: Preheat the oven to 350°F (176°C). Remove plastic wrap and place the casserole uncovered in the oven on the center rack. Bake for 35–40 minutes until the top is golden brown and a knife inserted near the center comes out mostly clean with a few moist crumbs. Make the streusel and finish baking: While the casserole bakes, prepare the streusel by cutting 1/2 cup cold salted butter into 3/4 cup all-purpose flour and 1/4–1/3 cup brown sugar with 1/2 teaspoon cinnamon until it resembles coarse crumbs. Sprinkle streusel evenly over the casserole in the final five minutes of baking, then return to the oven until the topping is just set and lightly browned. Rest and serve: Allow the dish to rest for 10–15 minutes out of the oven; this helps the custard set. Serve warm with maple syrup, a dusting of powdered sugar, or a dollop of whipped cream.

Storage Tips

Cool the casserole to room temperature for no more than two hours before refrigerating. Store tightly covered in the original baking dish with plastic wrap or transfer portions to airtight containers. In the fridge it will keep 3–4 days; warm individual portions in the oven at 325°F for 10–12 minutes to revive texture. For freezing, portion into single servings in freezer-safe containers or wrap the whole dish tightly in two layers of foil and plastic wrap; thaw in the refrigerator overnight and reheat in a 350°F oven until warmed through.

Ingredient Substitutions

To make this dairy-free, swap whole milk and heavy cream for equal parts unsweetened almond milk plus 2 tablespoons melted coconut oil, and use vegan butter for the streusel. For a gluten-free version, choose gluten-free bread and a 1:1 gluten-free flour blend for the streusel. If you prefer less sugar, reduce the granulated sugar in the custard to 1/3 cup — ripe bananas will make up some sweetness. To make it richer, substitute half the milk with evaporated milk or add one extra egg yolk to the custard.

Serving Suggestions

Serve warm with real maple syrup, a scoop of vanilla ice cream for brunch that borders on dessert, or a spoonful of Greek yogurt and toasted pecans for contrast. Fresh berries on the side add brightness, and a drizzle of browned butter syrup highlights the banana flavor. For a brunch buffet, pair with roasted coffee, a spinach salad, or savory frittatas to balance the sweet centerpiece.

Cultural Background

French toast has European roots but evolved in America into lavish baked versions designed to feed a crowd. This casserole borrows elements from bread puddings and classic French toast; it’s an Americanized comfort dish that became popular for large family gatherings and holiday breakfasts where hands-off overnight prep is a major advantage. Regional variations swap spices and fruit — apples or pears replace bananas in autumn adaptations.

Seasonal Adaptations

In autumn, add 1 cup diced apples and swap cinnamon for pumpkin pie spice. Summer calls for sliced strawberries or peaches folded in just before serving to keep them fresh. For winter holidays, add 1/4 cup raisins soaked in rum or 1/4 cup chopped toasted walnuts to the custard for texture and festive flavor.

Meal Prep Tips

Make a double batch and freeze one for a future occasion. Assemble the casserole in disposable foil pans if you plan to take it to a potluck — bake from refrigerated for about 45–50 minutes or from frozen at 350°F for 60–75 minutes, covered for the first 40 minutes. Portion into individual airtight containers for grab-and-go breakfasts and reheat quickly in the microwave or oven.

This casserole is the kind of dish that becomes part of weekend rituals: easy to assemble, impressive to serve, and forgiving in execution. Make it your own by adjusting sweetness, adding nuts, or swapping fruit — but keep that final streusel step; it’s what turns simple custardy bread into a brunch star.