Like a cross between a banana cream pie and a candy bar, the beloved British dessert known as banoffee pie beckons with sweet, creamy decadence: A crisp pastry shell overflows with a gooey, butterscotch-y filling; fresh sliced bananas; and clouds of coffee‑infused whipped cream.
Behind the Recipes
Crunchy, Creamy, Butterscotch-y: Banoffee Pie Has It All
This British treat layers fresh bananas and a butterscotch-y filling into a crisp cookie‑like crust and caps things off with billows of coffee-scented whipped cream.
By Published Aug. 7, 2023.
The recipe originated in the 70s with Ian Dowding (author of Fish Bananas [2020]) and the late Nigel Mackenzie (who owned the now-shuttered Hungry Monk restaurant in Sussex, England). Dowding, the restaurant’s head chef, was eager to explain the pie’s provenance on a video call from his home in Sussex.
“The filling should melt in the mouth.”
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As Dowding tells it, the cream, toffee, and coffee combination was inspired by the Coffee Toffee Pie from Blum’s, a bakery in San Francisco. After coming up with a preliminary recipe that incorporated those flavors, the pair experimented with introducing various nuts and fruits. When they tried bananas, it was a light-bulb moment: “You just know [when it’s right],” Dowding recalled. From then on, patrons wouldn’t let them take Banoffi Pie (now usually spelled “Banoffee”) off the menu.
Today, many variations on the recipe exist, and thankfully, I had Dowding’s blessing for putting my own spin on it and streamlining the preparation: “All chefs tweak, don’t they? That’s how things get invented.”
Science: What’s Baking Soda Doing in Banoffee Pie?
Baking soda may seem like an odd ingredient for a pie, but it plays a critical role in quickly transforming sweetened condensed milk into a golden-brown, flavorful filling: Soda increases the pH of the milk, catalyzing caramelization and the Maillard reaction. As the milk darkens, it absorbs heat faster and cooks faster. Baking soda also prevents the proteins in the milk from linking too tightly, so the chilled filling is silky, not solid.
Sweet as Pie
For the crust, Dowding calls for pâte sucrée, an egg-enriched French pastry dough that’s chilled before rolling. (He presses the dough into a tart pan, though the dessert is commonly referred to as a pie.) Others employ a crumb crust, but this seemed like a great application for the test kitchen’s trusted pat-in-the-pan dough. It has the crunchy, cookie-like appeal of pâte sucrée that would pair well with the gooey filling, but it’s almost effortless to prepare: Just stir melted butter together with flour, sugar, and salt; press the mixture into a tart pan; and bake.
Next, the filling, which can be the most time‑consuming part of the recipe. In most versions, including Dowding’s, it isn’t actually toffee, which is prepared by caramelizing sugar and butter, but rather, dulce de leche, a sort of milk jam that’s made by slowly cooking sweetened condensed milk to produce a rich toasted dairy flavor. Dowding prepares his by boiling unopened cans of the milk; others call for emptying cans into a baking dish and placing it in a water bath in the oven. After a few hours, the viscous, ivory liquid transforms into a tawny dulce de leche.
Motion Economy: Stir in A figure 8 Pattern
When you’re cooking something on the stovetop that requires constant stirring—such as banoffee pie filling, caramel, or roux—don’t move your spoon or spatula in a haphazard motion. To cover as much surface area as quickly as possible, swipe in a figure 8 pattern, which is the most efficient shape. I know because I tried every number from 0 to 9—and much of the alphabet too.
Hoping to speed things up, I poured a can of milk into a saucepan and simmered until it was golden brown. This took almost 30 minutes, but by then evaporation had caused it to harden like a rock. (When I cooked the milk less, it remained pale.)
To accelerate the process, some cooks incorporate dark brown sugar and butter. The former contributes molasses-y notes, so you don’t need as much caramelization; the latter helps the filling firm as it chills. And yet, without the nutty complexity produced by browning, the butter- and sugar-enhanced filling was tooth-achingly sweet.
Was there another way to speed things up? Senior Science Research Editor Paul Adams reminded me that baking soda can be used to hurry caramelization and Maillardization when making dulce de leche (see “What’s Baking Soda Doing in Banoffee Pie?”).
Keeping the butter and brown sugar in the pot, I added just ¼ teaspoon of baking soda to the milk (along with a sprinkle of salt to temper the sweetness). I couldn’t believe the results. Not only did the milk take on a deep hue within just 10 minutes, but its complexity and depth of flavor was unparalleled. This dulce de leche-esque filling was also more fluid in the pot, so it was easier to stir, and after refrigeration, it had a soft—not sticky—consistency.
It turns out that in addition to the browning and flavor boosts, the baking soda also prevented the proteins in the milk from linking as readily, so the glossy milk jam didn’t solidify too firmly.
Science: Banana Chemistry
If the aroma of a superripe banana reminds you of your last manicure, you’re not mistaken. The distinctive fragrance (and flavor) of fresh bananas is largely due to the organic compound isoamyl acetate, a molecule that’s used as a solvent (e.g., nail polish remover), added to perfumes, and mixed into artificial fruit flavorings. Isoamyl acetate is found in several flowers and fruits including pears—it even develops in beer—but it’s especially prominent in bananas, and it strengthens as the fruit ripens. The aroma of the compound in a tender‑firm banana will be just to enough to complement the buttery-sweet notes of a banoffee pie.
Bananas, Cream, and Coffee
Dowding recommends using bananas that have just started to speckle and I concur. Not only does the tender-firm fruit contrast the soft filling, but it’s not overly sweet. I sliced three bananas into thick rounds and arranged them on top of the filling where they waited for spoonfuls of lofty whipped cream.
On the subject of the whipped cream, a spoonful of espresso powder (along with touches of sugar and vanilla) brought intriguing bitterness that paired beautifully with the sweet, toasty notes of the filling. Whipping the cream to stiff—not soft—peaks gave it a bit of longevity, though it was still billowy—just right for a shower of shaved bittersweet chocolate.
I wished I could share a slice with Dowding, who still makes his banoffee pie for family and friends.
Recipe
Banoffee Pie
This British treat layers fresh bananas and a butterscotch-y filling into a crisp cookie-like crust and caps things off with billows of coffee-scented whipped cream.Get the Recipe
