The magic of this buttery, moist almond cake is two-fold: It comes together in just 10 minutes, and the almond flour-based batter is naturally gluten-free. As the cake bakes, the fresh berry topping sinks into the velvety, smooth crumb for bursts of hidden berry flavor.
Preheat the oven to 350°F.
Lightly grease an 8" round cake pan or line with a parchment round. Grease the parchment and sides of the pan to ensure the cake releases easily.
In a medium bowl, whisk together the almond flour, cornstarch, baking powder, and salt.
In another medium bowl or the bowl of your stand mixer, beat the butter, 1/2 cup (99g) of the sugar, and the lemon zest until fluffy and well combined, about 4 to 5 minutes. Add the egg yolks and extracts and beat until well combined, about 30 seconds.
Add the almond flour mixture to butter mixture and beat until just combined.
In a clean bowl with clean beaters, beat the egg whites and the remaining 2 tablespoons (25g) sugar to soft peaks, about 3 minutes.
Mix about 1/2 cup of the beaten egg whites into the almond flour mixture to loosen it. Then gently fold the remaining egg whites into the almond flour mixture, being careful not to deflate the egg whites (some lingering streaks are OK).
Transfer the batter to the prepared pan and smooth the top. Place the berries on top of the batter, spacing them evenly around the outer 3" of the pan. (As the cake bakes, the batter pushes the berries toward the middle. Starting with the berries around the edge of the pan will result in a more even distribution in the end.) There's no need to push the berries into the batter; they'll sink as the cake bakes.
Bake the cake for about 35 to 40 minutes, until golden brown and a toothpick or thin knife inserted into the center comes out with moist crumbs attached (rather than batter).
Let the cake cool in the pan on a wire rack for 10 minutes. Carefully flip the cake out of the pan, invert it onto a rack so that it’s right-side up, and let it cool completely. Dust with non-melting sugar or confectioners’ sugar before serving.
Store the almond flour cake, well-wrapped at room temperature, for several days.
For a plainer almond flour cake that you can top with whipped cream and fresh fruit or frost as a birthday cake, omit the lemon and berries.
