Peanut Butter Banana Cream Pie

Serves 8-10

If you combined all the best parts of Peanut Butter Pie and Banana Cream Pie, you’d get this.

A classic banana cream pie layered with salted peanut butter toffee sauce and a crunchy cornflake-and-peanut crust. Inspired by my sweet Papaw, who had an affinity for both bananas and peanut butter pie.

It starts with simple peanut butter toffee sauce that acts as the binder for the crust and forms the bottom layer of the pie. The salty, peanut-y, caramel-y flavor is the perfect pair to bananas and cream.

Like most banana cream pies, the filling begins with vanilla pastry cream. I turn it into crème diplomate (pastry cream folded with whipped cream) for a lighter, fluffier texture.

This pie requires a bit of patience and work, but the end result is absolutely worth it. And with bananas, peanut butter, and cereal, it’s also a pretty good excuse to have pie for breakfast.

WHAT YOU’LL NEED

INGREDIENTS

Peanut Butter Cornflake Crust

  • 3 ½ cups plain cornflakes (140 g)

  • ½ cup roasted salted peanuts, chopped small (70 g)

  • 6 tbsp unsalted butter (85 g)

  • ⅔ cup packed light brown sugar (135 g)

  • ¼ cup granulated sugar (50 g)

  • ¼ cup water (60 g)

  • 1 ½ tsp Diamond Crystal kosher salt (or ¾ tsp Morton kosher salt)

  • ½ cup conventional creamy peanut butter, not natural (135 g)

  • 1 ¼ tsp vanilla extract

  • For the Peanut Butter Sauce: 2 tbsp heavy cream (30 g)

Vanilla Diplomat Cream

  • 1 tsp powdered gelatin (3 g)

  • 1 tbsp cold water (15 g)

  • 1 large egg + 2 large egg yolks

  • ½ cup granulated sugar (100 g)

  • 1 ½ tbsp cornstarch (12 g)

  • ¼ tsp kosher salt

  • 1 cup whole milk (240 g)

  • 1 tbsp unsalted butter (14 g)

  • 1 tbsp vanilla bean paste or vanilla extract (15 g)

  • 1 cup cold heavy whipping cream (240 g)

For Assembly

  • 3-4 medium ripe bananas

DIRECTIONS

Make the Peanut Butter Cornflake Crust

  1. Preheat the oven to 325°F (165°C).

  2. Add the cornflakes to a large bowl. Crush them by hand until mostly broken up, with some small to medium pieces remaining. Stir in the chopped peanuts.

  3. In a medium saucepan, add the butter, brown sugar, granulated sugar, water, and salt and place over medium heat.

  4. Stir frequently until the butter melts and the mixture comes to a simmer. Once the mixture is bubbling, cook for about 2 minutes, then remove from the heat.

  5. Stir in the peanut butter and vanilla extract until completely smooth.

  6. Measure ¾ cup of the warm peanut butter mixture into a liquid measuring cup (set the rest aside for the Peanut Butter Sauce below). Pour it over the cornflakes and peanuts, tossing to coat evenly.

  7. Transfer the mixture to a 9-inch pie plate. Using the flat bottom of a measuring cup or glass, press firmly to compact the crust tightly against the bottom and sides of the pan.

    • Note: If the mixture is too crumbly to adhere when firmly pressed, stir in 1-2 tbsp of melted butter before pressing it into the pie plate.

  8. Bake for 12–13 minutes, until the crust is set and lightly golden.

  9. If needed, use the flat bottom of a measuring cup or glass to gently re-press any puffed or shifted areas immediately after removing the crust from the oven. Let cool completely.

Make the Peanut Butter Sauce

  1. While the remaining peanut butter mixture is still warm, thoroughly whisk in 2 tbsp of heavy cream until the sauce is silky, smooth, and completely emulsified.

  2. Set aside until the crust has cooled.

  3. Once the crust is cool, pour the sauce into the bottom of the crust, spreading it into an even layer. Refrigerate until the sauce is set and the vanilla diplomat is ready.

Make the Vanilla Diplomat Cream

  1. In a small bowl, sprinkle the gelatin over the cold water. Let stand for 5–10 minutes to bloom.

  2. In a medium heatproof bowl, whisk together the egg, egg yolks, granulated sugar, cornstarch, and salt until completely smooth.

  3. Heat the milk in a medium saucepan over medium heat until steaming but not boiling.

  4. Slowly pour a couple ladles of the hot milk into the egg mixture while whisking constantly.

  5. Pour the mixture back into the saucepan. Cook over medium heat, whisking constantly, until it thickens to a pudding-like consistency and begins to bubble.

  6. Remove from the heat. Immediately whisk in the bloomed gelatin until completely dissolved.

  7. Whisk in the butter and vanilla bean paste until smooth.

  8. Pour the pastry cream through a fine-mesh sieve into a large, clean bowl, using a spatula to press it through.

  9. Press plastic wrap directly against the surface to prevent a skin from forming. Refrigerate until completely cool, about 45 minutes to 1 hour.

  10. After chilling, re-whisk the pastry cream until smooth and creamy.

  11. In a stand mixer fitted with the whisk attachment or with an electric hand mixer, whip the cold heavy cream to medium peaks.

  12. Whisk the whipped cream into the pastry cream in two additions until smooth, light, and evenly incorporated.

Assemble the Pie

  1. Slice 2 bananas into approximately ¼-inch-thick coins. Reserve the remaining bananas for topping the pie just before serving to prevent browning.

  2. Arrange half of the banana coins in an even layer over the peanut butter sauce.

  3. Spread half of the vanilla diplomat cream over the bananas, smoothing the top with an offset spatula.

  4. Arrange the remaining banana slices in a second even layer.

  5. Top with the remaining diplomat cream and smooth the top.

  6. Refrigerate for at least 2 hours or overnight.

  7. Just before serving, top with the reserved sliced bananas and additional whipped cream, if desired. Serve cold.

RECIPE NOTES & TIPS

  • The pie can be assembled 1–2 days ahead and stored covered in the refrigerator. For the freshest appearance, add the whipped cream and any fresh banana garnish just before serving.

  • Totally optional but very fun: you can cut the banana slices into flowers like I did in the photo. I’ve linked the exact cookie cutter I used here.

  • Before starting the pastry cream, have all of your equipment ready. You’ll need a medium bowl, whisk, rubber spatula, ladle, small saucepan, and a fine-mesh strainer set over a clean bowl. Once the custard begins cooking, you’ll need to whisk constantly and won’t want to step away.

  • The cornflake crust is intentionally rustic and crunchy, so it won’t compact as smoothly as a graham cracker crust. It may feel slightly loose before baking, but it firms considerably once baked and chilled. If you’re struggling to get the mixture to hold together in the pie plate, stir in 1–2 tbsp of melted butter before pressing.

  • To bake as consistently as possible, I recommend using a Digital Food Scale. The one I linked is relatively inexpensive and, in my opinion, a great investment for any home kitchen. If you don’t have one, cup measurements are included as well.