Recipe: Coffee and Walnut Cake
When a celebration is in the air, British thoughts turn naturally to layer cakes. They are a little more work, as you have to attend to both cake and frosting, but there’s still no need to go overboard on the panic and piping bags — unless you want to. We’ll often just swirl the frosting over the cake with the back of a spoon and call it done.
If we’re being honest the coffee and walnut cake, in all its varying shades of anemic brown, is not the most attractive cake — but here the pleasure lies all in the flavor, which is utterly sublime. British food writer Nigel Slater has gone so far as to say that coffee and walnut cake would be his last meal on earth, and it’s definitely an idea with considerable merit.
The delicate sponge and silky buttercream are both threaded through with toasty, caramel flavors, until it is impossible to tell where the walnuts end and the coffee begins. Everything just melds into one scrumptious whole.
Found in teashops across the land, the flavors of this not-too-sweet cake are quite sophisticated. It doesn’t lend itself well to sprinkles, so I usually make this to celebrate grown-ups. In Britain the coffee taste is often imparted by old-fashioned Camp coffee essence, which mostly still exists to make this cake.
Here in the U.S. I used powdered coffee, as it is difficult to make espresso strong enough so that the flavor shines through without making the batter too wet. A touch of buttermilk in the batter to lighten the nutty sponge, and a hint of maple syrup in the frosting are both ideas I got from American baking — although not traditional, they work extremely well.
When it comes to British baking there’s cake and everything else. From afternoon tea to an exuberant birthday cake to the classic Vicky sponge, baking cake is a national pastime. We teamed up with ex-pat Paola Thomas to bring you five favorite cakes that you can whip up in a jiffy.
Coffee and Walnut Cake
Serves8 to 10
For the coffee and walnut sponge:
- 1 1/2 cups
all-purpose or cake flour
- 1/2 cup
- 1 1/2 teaspoons
- 1/2 teaspoon
- 1/4 teaspoon
- 2 sticks
(8 ounces) unsalted butter, at room temperature, plus more for coating the cake pans
- 3/4 cup
- 1/4 cup
packed light brown sugar
- 1 cup
walnut pieces, finely chopped
- 1/2 cup
- 4 teaspoons
instant coffee powder or granules, dissolved in 1 tablespoon hot water (or 1 shot extra-strong espresso)
- 1 to 2 tablespoons
For the coffee buttercream:
- 6 cups
powdered sugar (1 pound, 10 ounces), sifted
- 3 sticks
(12 ounces) unsalted butter, at room temperature
- 1/4 teaspoon
- 2 tablespoons
- 1 tablespoon
instant coffee powder or granules, dissolved in 1 tablespoon hot water (or 1 shot of extra-strong espresso), cooled to room temperature
- 1 tablespoon
Walnut halves, for decorating (optional)
Make the cake:
Arrange a rack in the middle of the oven and heat to 325°F. Coat 2 (8-inch) round cake pans with butter, then line the bottoms with parchment paper.
Place the flour, almond flour, baking powder, baking soda, and salt in a medium bowl and whisk to combine; set aside.
Place the butter, granulated sugar, and brown sugar in a stand mixer fitted with the paddle attachment. Beat on medium speed until very pale and fluffy, 3 to 5 minutes, scraping down the sides of the bowl as needed; set aside.
Stir the walnuts into the butter mixture. Add 1 of the eggs and a spoonful of the flour mixture into the butter mixture and beat to combine. Repeat with the remaining eggs, accompanying each egg with a spoonful of flour and beating thoroughly and scraping down the sides of the bowl with a rubber spatula between each addition.
Add the remaining flour mixture, buttermilk, and coffee and gently fold with a metal spoon or plastic spatula to combine. You should end up with a mousse-like batter that slides reluctantly off a downward-pointing metal spoon. This is called "dropping consistency." If necessary, add a tablespoon or two of hot water to get the consistency right.
Divide the batter equally between the two cake pans, spreading it right to the edges and smoothing out the top with the spatula.
Bake until the cakes are golden, firm and springy, and starting to pull away from the sides, 30 to 35 minutes. A fingertip pressed gently on the top of the cake should leave no imprint. Let the cakes cool in the pans on wire racks for 5 minutes. Run a small metal spatula or thin knife around the edges of the cakes, then flip them out onto the rack to cool comletely.
Make the buttercream:
Place the powdered sugar, butter, and salt in the bowl of a stand mixer fitted with the paddle attachment. Beat on medium speed until very pale and fluffy, 3 to 5 minutes. Beat in the cream, coffee, and maple syrup.
Dollop about 1/3 of the frosting on one cake layer and spread evenly. Top with the second cake layer. Dollop the remaining frosting on the top of the cake, then spread to evenly cover the top and the sides. Decorate with the walnut halves if desired.
Storage: Although best eaten as fresh as possible, you can store any leftover cake in an airtight container in the refrigerator for up to 4 days.
Make ahead: The unfrosted cake layers will freeze beautifully, ready to be defrosted and filled on the day you plan to assemble and serve.